Support

OpenShift Container Platform 4.6

Getting support for OpenShift Container Platform

Red Hat OpenShift Documentation Team

Abstract

This document provides information on getting support from Red Hat for OpenShift Container Platform. It also contains information about remote health monitoring through Telemetry and the Insights Operator. The document also details the benefits that remote health monitoring provides.

Chapter 1. Getting support

1.1. Getting support

If you experience difficulty with a procedure described in this documentation, or with OpenShift Container Platform in general, visit the Red Hat Customer Portal. From the Customer Portal, you can:

  • Search or browse through the Red Hat Knowledgebase of articles and solutions relating to Red Hat products.
  • Submit a support case to Red Hat Support.
  • Access other product documentation.

To identify issues with your cluster, you can use Insights in Red Hat OpenShift Cluster Manager. Insights provides details about issues and, if available, information on how to solve a problem.

If you have a suggestion for improving this documentation or have found an error, please submit a Bugzilla report against the OpenShift Container Platform product for the Documentation component. Please provide specific details, such as the section name and OpenShift Container Platform version.

1.2. About the Red Hat Knowledgebase

The Red Hat Knowledgebase provides rich content aimed at helping you make the most of Red Hat’s products and technologies. The Red Hat Knowledgebase consists of articles, product documentation, and videos outlining best practices on installing, configuring, and using Red Hat products. In addition, you can search for solutions to known issues, each providing concise root cause descriptions and remedial steps.

1.3. Searching the Red Hat Knowledgebase

In the event of an OpenShift Container Platform issue, you can perform an initial search to determine if a solution already exists within the Red Hat Knowledgebase.

Prerequisites

  • You have a Red Hat Customer Portal account.

Procedure

  1. Log in to the Red Hat Customer Portal.
  2. In the main Red Hat Customer Portal search field, input keywords and strings relating to the problem, including:

    • OpenShift Container Platform components (such as etcd)
    • Related procedure (such as installation)
    • Warnings, error messages, and other outputs related to explicit failures
  3. Click Search.
  4. Select the OpenShift Container Platform product filter.
  5. Select the Knowledgebase content type filter.

1.4. Submitting a support case

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have a Red Hat Customer Portal account.
  • You have a Red Hat standard or premium Subscription.

Procedure

  1. Log in to the Red Hat Customer Portal and select SUPPORT CASESOpen a case.
  2. Select the appropriate category for your issue (such as Defect / Bug), product (OpenShift Container Platform), and product version (4.6, if this is not already autofilled).
  3. Review the list of suggested Red Hat Knowledgebase solutions for a potential match against the problem that is being reported. If the suggested articles do not address the issue, click Continue.
  4. Enter a concise but descriptive problem summary and further details about the symptoms being experienced, as well as your expectations.
  5. Review the updated list of suggested Red Hat Knowledgebase solutions for a potential match against the problem that is being reported. The list is refined as you provide more information during the case creation process. If the suggested articles do not address the issue, click Continue.
  6. Ensure that the account information presented is as expected, and if not, amend accordingly.
  7. Check that the autofilled OpenShift Container Platform Cluster ID is correct. If it is not, manually obtain your cluster ID.

    • To manually obtain your cluster ID using the OpenShift Container Platform web console:

      1. Navigate to HomeDashboardsOverview.
      2. Find the value in the Cluster ID field of the Details section.
    • Alternatively, it is possible to open a new support case through the OpenShift Container Platform web console and have your cluster ID autofilled.

      1. From the toolbar, navigate to (?) HelpOpen Support Case.
      2. The Cluster ID value is autofilled.
    • To obtain your cluster ID using the OpenShift CLI (oc), run the following command:

      $ oc get clusterversion -o jsonpath='{.items[].spec.clusterID}{"\n"}'
  8. Complete the following questions where prompted and then click Continue:

    • Where are you experiencing the behavior? What environment?
    • When does the behavior occur? Frequency? Repeatedly? At certain times?
    • What information can you provide around time-frames and the business impact?
  9. Upload relevant diagnostic data files and click Continue. It is recommended to include data gathered using the oc adm must-gather command as a starting point, plus any issue specific data that is not collected by that command.
  10. Input relevant case management details and click Continue.
  11. Preview the case details and click Submit.

1.5. Additional resources

Chapter 2. Remote health monitoring with connected clusters

2.1. About remote health monitoring

OpenShift Container Platform collects telemetry and configuration data about your cluster and reports it to Red Hat by using the Telemeter Client and the Insights Operator. The data that is provided to Red Hat enables the benefits outlined in this document.

A cluster that reports data to Red Hat through Telemetry and the Insights Operator is considered a connected cluster.

Telemetry is the term that Red Hat uses to describe the information being sent to Red Hat by the OpenShift Container Platform Telemeter Client. Lightweight attributes are sent from connected clusters to Red Hat to enable subscription management automation, monitor the health of clusters, assist with support, and improve customer experience.

The Insights Operator gathers OpenShift Container Platform configuration data and sends it to Red Hat. The data is used to produce insights about potential issues that a cluster might be exposed to. These insights are communicated to cluster administrators on cloud.redhat.com/openshift.

More information is provided in this document about these two processes.

Telemetry and Insights Operator benefits

Telemetry and the Insights Operator enable the following benefits for end-users:

  • Enhanced identification and resolution of issues. Events that might seem normal to an end-user can be observed by Red Hat from a broader perspective across a fleet of clusters. Some issues can be more rapidly identified from this point of view and resolved without an end-user needing to open a support case or file a Bugzilla.
  • Advanced release management. OpenShift Container Platform offers the candidate, fast, and stable release channels, which enable you to choose an update strategy. The graduation of a release from fast to stable is dependent on the success rate of updates and on the events seen during upgrades. With the information provided by connected clusters, Red Hat can improve the quality of releases to stable channels and react more rapidly to issues found in the fast channels.
  • Targeted prioritization of new features and functionality. The data collected provides insights about which areas of OpenShift Container Platform are used most. With this information, Red Hat can focus on developing the new features and functionality that have the greatest impact for our customers.
  • A streamlined support experience. You can provide a cluster ID for a connected cluster when creating a support ticket on the Red Hat Customer Portal. This enables Red Hat to deliver a streamlined support experience that is specific to your cluster, by using the connected information. This document provides more information about that enhanced support experience.
  • Predictive analytics. The insights displayed for your cluster on cloud.redhat.com/openshift are enabled by the information collected from connected clusters. Red Hat is investing in applying deep learning, machine learning, and artificial intelligence automation to help identify issues that OpenShift Container Platform clusters are exposed to.

2.1.1. About Telemetry

Telemetry sends a carefully chosen subset of the cluster monitoring metrics to Red Hat. The Telemeter Client fetches the metrics values every four minutes and thirty seconds and uploads the data to Red Hat. These metrics are described in this document.

This stream of data is used by Red Hat to monitor the clusters in real-time and to react as necessary to problems that impact our customers. It also allows Red Hat to roll out OpenShift Container Platform upgrades to customers to minimize service impact and continuously improve the upgrade experience.

This debugging information is available to Red Hat Support and Engineering teams with the same restrictions as accessing data reported through support cases. All connected cluster information is used by Red Hat to help make OpenShift Container Platform better and more intuitive to use.

Additional resources

2.1.1.1. Information collected by Telemetry

The following information is collected by Telemetry:

  • The unique random identifier that is generated during an installation
  • Version information, including the OpenShift Container Platform cluster version and installed update details that are used to determine update version availability
  • Update information, including the number of updates available per cluster, the channel and image repository used for an update, update progress information, and the number of errors that occur in an update
  • The name of the provider platform that OpenShift Container Platform is deployed on and the data center location
  • Sizing information about clusters, machine types, and machines, including the number of CPU cores and the amount of RAM used for each
  • The number of etcd members and the number of objects stored in the etcd cluster
  • The OpenShift Container Platform framework components installed in a cluster and their condition and status
  • Usage information about components, features, and extensions
  • Usage details about Technology Previews and unsupported configurations
  • Information about degraded software
  • Information about nodes that are marked as NotReady
  • Events for all namespaces listed as "related objects" for a degraded Operator
  • Configuration details that help Red Hat Support to provide beneficial support for customers. This includes node configuration at the cloud infrastructure level, host names, IP addresses, Kubernetes pod names, namespaces, and services.
  • Information about the validity of certificates

Telemetry does not collect identifying information such as user names, or passwords. Red Hat does not intend to collect personal information. If Red Hat discovers that personal information has been inadvertently received, Red Hat will delete such information. To the extent that any telemetry data constitutes personal data, please refer to the Red Hat Privacy Statement for more information about Red Hat’s privacy practices.

Additional resources

2.1.2. About the Insights Operator

The Insights Operator periodically gathers configuration and component failure status and, by default, reports that data every two hours to Red Hat. This information enables Red Hat to assess configuration and deeper failure data than is reported through Telemetry.

Users of OpenShift Container Platform can display the report of each cluster in Red Hat OpenShift Cluster Manager. If any issues have been identified, Insights provides further details and, if available, steps on how to solve a problem.

The Insights Operator does not collect identifying information, such as user names, passwords, or certificates. See Red Hat Insights Data & Application Security for information about Red Hat Insights data collection and controls.

Red Hat uses all connected cluster information to:

  • Proactively identify potential cluster issues and provide a solution and preventive actions in Red Hat OpenShift Cluster Manager
  • Improve OpenShift Container Platform by providing aggregated and critical information to product and support teams
  • Make OpenShift Container Platform more intuitive

Additional resources

2.1.2.1. Information collected by the Insights Operator

The following information is collected by the Insights Operator:

  • General information about your cluster and its components to identify issues that are specific to your OpenShift Container Platform version and environment
  • Configuration files, such as the image registry configuration, of your cluster to determine incorrect settings and issues that are specific to parameters you set
  • Errors that occur in the cluster components
  • Progress information of running updates, and the status of any component upgrades
  • Details of the platform that OpenShift Container Platform is deployed on, such as Amazon Web Services, and the region that the cluster is located in
  • If an Operator reports an issue, information is collected about core OpenShift Container Platform pods in the openshift-* and kube-* projects. This includes state, resource, security context, volume information, and more.

Additional resources

2.1.3. Understanding Telemetry and Insights Operator data flow

The Telemeter Client collects selected time series data from the Prometheus API. The time series data is uploaded to api.openshift.com every four minutes and thirty seconds for processing.

The Insights Operator gathers selected data from the Kubernetes API and the Prometheus API into an archive. The archive is uploaded to cloud.redhat.com every two hours for processing. The Insights Operator also downloads the latest Insights analysis from cloud.redhat.com. This is used to populate the Insights status pop-up that is included in the Overview page in the OpenShift Container Platform web console.

All of the communication with Red Hat occurs over encrypted channels by using Transport Layer Security (TLS) and mutual certificate authentication. All of the data is encrypted in transit and at rest.

Access to the systems that handle customer data is controlled through multi-factor authentication and strict authorization controls. Access is granted on a need-to-know basis and is limited to required operations.

Telemetry and Insights Operator data flow

Additional resources

2.1.4. Additional details about how remote health monitoring data is used

The information collected to enable remote health monitoring is detailed in Information collected by Telemetry and Information collected by the Insights Operator.

As further described in the preceding sections of this document, Red Hat collects data about your use of the Red Hat Product(s) for purposes such as providing support and upgrades, optimizing performance or configuration, minimizing service impacts, identifying and remediating threats, troubleshooting, improving the offerings and user experience, responding to issues, and for billing purposes if applicable.

Collection safeguards

Red Hat employs technical and organizational measures designed to protect the telemetry and configuration data.

Sharing

Red Hat may share the data collected through Telemetry and the Insights Operator internally within Red Hat to improve your user experience. Red Hat may share telemetry and configuration data with its business partners in an aggregated form that does not identify customers to help the partners better understand their markets and their customers’ use of Red Hat offerings or to ensure the successful integration of products jointly supported by those partners.

Third party service providers

Red Hat may engage certain service providers to assist in the collection and storage of the telemetry and configuration data.

User control / enabling and disabling telemetry and configuration data collection

You may disable OpenShift Container Platform Telemetry and the Insights Operator by following the instructions in Opting out of remote health reporting.

2.2. Showing data collected by remote health monitoring

As an administrator, you can review the metrics collected by Telemetry and the Insights Operator.

2.2.1. Showing data collected by Telemetry

You can see the cluster and components time series data captured by Telemetry.

Prerequisites

  • Install the OpenShift CLI (oc).
  • You must log in to the cluster with a user that has either the cluster-admin role or the cluster-monitoring-view role.

Procedure

  1. Find the URL for the Prometheus service that runs in the OpenShift Container Platform cluster:

    $ oc get route prometheus-k8s -n openshift-monitoring -o jsonpath="{.spec.host}"
  2. Navigate to the URL.
  3. Enter this query in the Expression input box and press Execute:

    {__name__=~"cluster:usage:.*|count:up0|count:up1|cluster_version|cluster_version_available_updates|cluster_operator_up|cluster_operator_conditions|cluster_version_payload|cluster_installer|cluster_infrastructure_provider|cluster_feature_set|instance:etcd_object_counts:sum|ALERTS|code:apiserver_request_total:rate:sum|cluster:capacity_cpu_cores:sum|cluster:capacity_memory_bytes:sum|cluster:cpu_usage_cores:sum|cluster:memory_usage_bytes:sum|openshift:cpu_usage_cores:sum|openshift:memory_usage_bytes:sum|workload:cpu_usage_cores:sum|workload:memory_usage_bytes:sum|cluster:virt_platform_nodes:sum|cluster:node_instance_type_count:sum|cnv:vmi_status_running:count|node_role_os_version_machine:cpu_capacity_cores:sum|node_role_os_version_machine:cpu_capacity_sockets:sum|subscription_sync_total|csv_succeeded|csv_abnormal|ceph_cluster_total_bytes|ceph_cluster_total_used_raw_bytes|ceph_health_status|job:ceph_osd_metadata:count|job:kube_pv:count|job:ceph_pools_iops:total|job:ceph_pools_iops_bytes:total|job:ceph_versions_running:count|job:noobaa_total_unhealthy_buckets:sum|job:noobaa_bucket_count:sum|job:noobaa_total_object_count:sum|noobaa_accounts_num|noobaa_total_usage|console_url|cluster:network_attachment_definition_instances:max|cluster:network_attachment_definition_enabled_instance_up:max|insightsclient_request_send_total|cam_app_workload_migrations|cluster:apiserver_current_inflight_requests:sum:max_over_time:2m|cluster:telemetry_selected_series:count",alertstate=~"firing|"}

    This query replicates the request that Telemetry makes against a running OpenShift Container Platform cluster’s Prometheus service and returns the full set of time series captured by Telemetry.

2.2.2. Showing data collected by the Insights Operator

You can review the data that is collected by the Insights Operator.

Prerequisites

  • Access to the cluster as a user with the cluster-admin role.

Procedure

  1. Find the name of the currently running pod for the Insights Operator:

    $ INSIGHTS_OPERATOR_POD=$(oc get pods --namespace=openshift-insights -o custom-columns=:metadata.name --no-headers  --field-selector=status.phase=Running)
  2. Copy the recent data archives collected by the Insights Operator:

    $ oc cp openshift-insights/$INSIGHTS_OPERATOR_POD:/var/lib/insights-operator ./insights-data

The recent Insights Operator archives are now available in the insights-data directory.

2.3. Opting out of remote health reporting

You may choose to opt out of reporting health and usage data for your cluster.

To opt out of remote health reporting, you must:

  1. Modify the global cluster pull secret to disable remote health reporting.
  2. Update the cluster to use this modified pull secret.

2.3.1. Consequences of disabling remote health reporting

In OpenShift Container Platform, customers can opt out of reporting usage information. However, connected clusters allow Red Hat to react more quickly to problems and better support our customers, as well as better understand how product upgrades impact clusters. Connected clusters also help to simplify the subscription and entitlement process and enable the Red Hat OpenShift Cluster Manager service to provide an overview of your clusters and their subscription status.

Red Hat strongly recommends leaving health and usage reporting enabled for pre-production and test clusters even if it is necessary to opt out for production clusters. This allows Red Hat to be a participant in qualifying OpenShift Container Platform in your environments and react more rapidly to product issues.

Some of the consequences of opting out of having a connected cluster are:

  • Red Hat will not be able to monitor the success of product upgrades or the health of your clusters without a support case being opened.
  • Red Hat will not be able to use configuration data to better triage customer support cases and identify which configurations our customers find important.
  • The Red Hat OpenShift Cluster Manager will not show data about your clusters including health and usage information.
  • Your subscription entitlement information must be manually entered via cloud.redhat.com without the benefit of automatic usage reporting.

In restricted networks, Telemetry and Insights data can still be reported through appropriate configuration of your proxy.

2.3.2. Modifying the global cluster pull secret to disable remote health reporting

You can modify your existing global cluster pull secret to disable remote health reporting. This disables both Telemetry and the Insights Operator.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.

Procedure

  1. Download the global cluster pull secret to your local file system.

    $ oc extract secret/pull-secret -n openshift-config --to=.
  2. In a text editor, edit the .dockerconfigjson file that was downloaded.
  3. Remove the cloud.openshift.com JSON entry, for example:

    "cloud.openshift.com":{"auth":"<hash>","email":"<email_address>"}
  4. Save the file.

You can now update your cluster to use this modified pull secret.

2.3.3. Updating the global cluster pull secret

You can update the global pull secret for your cluster.

Warning

Cluster resources must adjust to the new pull secret, which can temporarily limit the usability of the cluster.

Warning

Updating the global pull secret will cause node reboots while the Machine Config Operator (MCO) syncs the changes.

Prerequisites

  • You have a new or modified pull secret file to upload.
  • You have access to the cluster as a user with the cluster-admin role.

Procedure

  • Enter the following command to update the global pull secret for your cluster:

    $ oc set data secret/pull-secret -n openshift-config --from-file=.dockerconfigjson=<pull-secret-location> 1
    1
    Provide the path to the new pull secret file.

This update is rolled out to all nodes, which can take some time depending on the size of your cluster. During this time, nodes are drained and pods are rescheduled on the remaining nodes.

2.4. Using Insights to identify issues with your cluster

Insights repeatedly analyzes the data Insights Operator sends. Users of OpenShift Container Platform can display the report on the Insights tab of each cluster in Red Hat OpenShift Cluster Manager.

2.4.1. Displaying potential issues with your cluster

This section describes how to display the Insights report in the Red Hat OpenShift Cluster Manager.

Note that Insights repeatedly analyzes your cluster and shows the latest results. These results can change, for example, if you fix an issue or a new issue has been detected.

Prerequisites

  • Your cluster is registered in the Red Hat OpenShift Cluster Manager.
  • Remote health reporting is enabled, which is the default.
  • You are logged in to the Red Hat OpenShift Cluster Manager.

Procedure

  1. Click the Clusters menu in the left pane.
  2. Click the cluster’s name to display the details of the cluster.
  3. Open the Insights tab of the cluster.

    Depending on the result, the tab displays one of the following:

    • Your cluster passed all health checks, if Insights did not identify any issues.
    • A list of issues Insights has detected, prioritized by risk (low, moderate, important, and critical).
    • No health checks to display, if Insights has not yet analyzed the cluster. The analysis starts shortly after the cluster has been installed and connected to the internet.
  4. If any issues are displayed on the tab, click the > icon in front of the entry for further details.

    Depending on the issue, the details can also contain a link to an Red Hat Knowledge Base article. For details and information on how to solve the problem, click How to remediate this issue.

2.5. Using remote health reporting in a restricted network

You can manually gather and upload Insights Operator archives to diagnose issues from a restricted network.

To use the Insights Operator in a restricted network, you must:

  • Create a copy of your Insights Operator archive.
  • Upload the Insights Operator archive to cloud.redhat.com.

2.5.1. Copying an Insights Operator archive

You must create a copy of your Insights Operator data archive for upload to cloud.redhat.com.

Prerequisites

  • You are logged in to OpenShift Container Platform as cluster-admin.

Procedure

  1. Find the name of the Insights Operator pod that is currently running:

    $ INSIGHTS_OPERATOR_POD=$(oc get pods --namespace=openshift-insights -o custom-columns=:metadata.name --no-headers  --field-selector=status.phase=Running)
  2. Copy the recent data archives from the Insights Operator container:

    $ oc cp openshift-insights/$INSIGHTS_OPERATOR_POD:/var/lib/insights-operator ./insights-data

The recent Insights Operator archives are now available in the insights-data directory.

2.5.2. Uploading an Insights Operator archive

You can manually upload an Insights Operator archive to cloud.redhat.com to diagnose potential issues.

Prerequisites

  • You are logged in to OpenShift Container Platform as cluster-admin.
  • You have a workstation with unrestricted internet access.
  • You have created a copy of the Insights Operator archive.

Procedure

  1. Download the dockerconfig.json file:

    $ oc extract secret/pull-secret -n openshift-config --to=.
  2. Copy your "cloud.openshift.com" "auth" token from the dockerconfig.json file:

    {
      "auths": {
        "cloud.openshift.com": {
          "auth": "<your_token>",
          "email": "asd@redhat.com"
        }
    }
  3. Upload the archive to cloud.redhat.com:

    $ curl -v -H "User-Agent: insights-operator/one10time200gather184a34f6a168926d93c330 cluster/<cluster_id>" -H "Authorization: Bearer <your_token>" -F "upload=@<path_to_archive>; type=application/vnd.redhat.openshift.periodic+tar" https://cloud.redhat.com/api/ingress/v1/upload

    where <cluster_id> is your cluster ID, <your_token> is the token from your pull secret, and <path_to_archive> is the path to the Insights Operator archive.

    If the operation is successful, the command returns a "request_id" and "account_number":

    Example output

    * Connection #0 to host cloud.redhat.com left intact
    {"request_id":"393a7cf1093e434ea8dd4ab3eb28884c","upload":{"account_number":"6274079"}}%

Verification steps

  1. Log in to https://cloud.redhat.com/openshift.
  2. Click the Clusters menu in the left pane.
  3. To display the details of the cluster, click the cluster name.
  4. Open the Insights Advisor tab of the cluster.

    If the upload was successful, the tab displays one of the following:

    • Your cluster passed all recommendations, if Insights Advisor did not identify any issues.
    • A list of issues that Insights Advisor has detected, prioritized by risk (low, moderate, important, and critical).

Chapter 3. Gathering data about your cluster

When opening a support case, it is helpful to provide debugging information about your cluster to Red Hat Support.

It is recommended to provide:

3.1. About the must-gather tool

The oc adm must-gather CLI command collects the information from your cluster that is most likely needed for debugging issues, such as:

  • Resource definitions
  • Audit logs
  • Service logs

You can specify one or more images when you run the command by including the --image argument. When you specify an image, the tool collects data related to that feature or product.

When you run oc adm must-gather, a new pod is created on the cluster. The data is collected on that pod and saved in a new directory that starts with must-gather.local. This directory is created in the current working directory.

3.2. Gathering data about your cluster for Red Hat Support

You can gather debugging information about your cluster by using the oc adm must-gather CLI command.

Prerequisites

  • Access to the cluster as a user with the cluster-admin role.
  • The OpenShift Container Platform CLI (oc) installed.

Procedure

  1. Navigate to the directory where you want to store the must-gather data.
  2. Run the oc adm must-gather command:

    $ oc adm must-gather
    Note

    If this command fails, for example if you cannot schedule a pod on your cluster, then use the oc adm inspect command to gather information for particular resources. Contact Red Hat Support for the recommended resources to gather.

    Note

    If your cluster is using a restricted network, you must take additional steps. If your mirror registry has a trusted CA, you must first add the trusted CA to the cluster. For all clusters on restricted networks, you must import the default must-gather image as an image stream before you use the oc adm must-gather command.

    $ oc import-image is/must-gather -n openshift
  3. Create a compressed file from the must-gather directory that was just created in your working directory. For example, on a computer that uses a Linux operating system, run the following command:

    $ tar cvaf must-gather.tar.gz must-gather.local.5421342344627712289/ 1
    1
    Make sure to replace must-gather-local.5421342344627712289/ with the actual directory name.
  4. Attach the compressed file to your support case on the Red Hat Customer Portal.

3.3. Gathering data about specific features

You can gather debugging information about specific features by using the oc adm must-gather CLI command with the --image or --image-stream argument. The must-gather tool supports multiple images, so you can gather data about more than one feature by running a single command.

Table 3.1. Supported must-gather images

ImagePurpose

registry.redhat.io/container-native-virtualization/cnv-must-gather-rhel8:v2.5.6

Data collection for OpenShift Virtualization.

registry.redhat.io/openshift-serverless-1/svls-must-gather-rhel8

Data collection for OpenShift Serverless.

registry.redhat.io/openshift-service-mesh/istio-must-gather-rhel8

Data collection for Red Hat OpenShift Service Mesh.

registry.redhat.io/rhmtc/openshift-migration-must-gather-rhel8:v1.4

Data collection for the Migration Toolkit for Containers.

registry.redhat.io/ocs4/ocs-must-gather-rhel8:v4.6

Data collection for Red Hat OpenShift Container Storage.

registry.redhat.io/openshift4/ose-cluster-logging-operator

Data collection for Red Hat OpenShift cluster logging.

Note

To collect the default must-gather data in addition to specific feature data, add the --image-stream=openshift/must-gather argument.

Prerequisites

  • Access to the cluster as a user with the cluster-admin role.
  • The OpenShift Container Platform CLI (oc) installed.

Procedure

  1. Navigate to the directory where you want to store the must-gather data.
  2. Run the oc adm must-gather command with one or more --image or --image-stream arguments. For example, the following command gathers both the default cluster data and information specific to OpenShift Virtualization:

    $ oc adm must-gather \
     --image-stream=openshift/must-gather \ 1
     --image=registry.redhat.io/container-native-virtualization/cnv-must-gather-rhel8:v2.5.6 2
    1
    The default OpenShift Container Platform must-gather image
    2
    The must-gather image for OpenShift Virtualization

    You can use the must-gather tool with additional arguments to gather data that is specifically related to cluster logging and the Cluster Logging Operator in your cluster. For cluster logging, run the following command:

    $ oc adm must-gather --image=$(oc -n openshift-logging get deployment.apps/cluster-logging-operator \
     -o jsonpath='{.spec.template.spec.containers[?(@.name == "cluster-logging-operator")].image}')

    Example 3.1. Example must-gather output for cluster logging

    ├── cluster-logging
    │  ├── clo
    │  │  ├── cluster-logging-operator-74dd5994f-6ttgt
    │  │  ├── clusterlogforwarder_cr
    │  │  ├── cr
    │  │  ├── csv
    │  │  ├── deployment
    │  │  └── logforwarding_cr
    │  ├── collector
    │  │  ├── fluentd-2tr64
    │  ├── curator
    │  │  └── curator-1596028500-zkz4s
    │  ├── eo
    │  │  ├── csv
    │  │  ├── deployment
    │  │  └── elasticsearch-operator-7dc7d97b9d-jb4r4
    │  ├── es
    │  │  ├── cluster-elasticsearch
    │  │  │  ├── aliases
    │  │  │  ├── health
    │  │  │  ├── indices
    │  │  │  ├── latest_documents.json
    │  │  │  ├── nodes
    │  │  │  ├── nodes_stats.json
    │  │  │  └── thread_pool
    │  │  ├── cr
    │  │  ├── elasticsearch-cdm-lp8l38m0-1-794d6dd989-4jxms
    │  │  └── logs
    │  │     ├── elasticsearch-cdm-lp8l38m0-1-794d6dd989-4jxms
    │  ├── install
    │  │  ├── co_logs
    │  │  ├── install_plan
    │  │  ├── olmo_logs
    │  │  └── subscription
    │  └── kibana
    │     ├── cr
    │     ├── kibana-9d69668d4-2rkvz
    ├── cluster-scoped-resources
    │  └── core
    │     ├── nodes
    │     │  ├── ip-10-0-146-180.eu-west-1.compute.internal.yaml
    │     └── persistentvolumes
    │        ├── pvc-0a8d65d9-54aa-4c44-9ecc-33d9381e41c1.yaml
    ├── event-filter.html
    ├── gather-debug.log
    └── namespaces
       ├── openshift-logging
       │  ├── apps
       │  │  ├── daemonsets.yaml
       │  │  ├── deployments.yaml
       │  │  ├── replicasets.yaml
       │  │  └── statefulsets.yaml
       │  ├── batch
       │  │  ├── cronjobs.yaml
       │  │  └── jobs.yaml
       │  ├── core
       │  │  ├── configmaps.yaml
       │  │  ├── endpoints.yaml
       │  │  ├── events
       │  │  │  ├── curator-1596021300-wn2ks.162634ebf0055a94.yaml
       │  │  │  ├── curator.162638330681bee2.yaml
       │  │  │  ├── elasticsearch-delete-app-1596020400-gm6nl.1626341a296c16a1.yaml
       │  │  │  ├── elasticsearch-delete-audit-1596020400-9l9n4.1626341a2af81bbd.yaml
       │  │  │  ├── elasticsearch-delete-infra-1596020400-v98tk.1626341a2d821069.yaml
       │  │  │  ├── elasticsearch-rollover-app-1596020400-cc5vc.1626341a3019b238.yaml
       │  │  │  ├── elasticsearch-rollover-audit-1596020400-s8d5s.1626341a31f7b315.yaml
       │  │  │  ├── elasticsearch-rollover-infra-1596020400-7mgv8.1626341a35ea59ed.yaml
       │  │  ├── events.yaml
       │  │  ├── persistentvolumeclaims.yaml
       │  │  ├── pods.yaml
       │  │  ├── replicationcontrollers.yaml
       │  │  ├── secrets.yaml
       │  │  └── services.yaml
       │  ├── openshift-logging.yaml
       │  ├── pods
       │  │  ├── cluster-logging-operator-74dd5994f-6ttgt
       │  │  │  ├── cluster-logging-operator
       │  │  │  │  └── cluster-logging-operator
       │  │  │  │     └── logs
       │  │  │  │        ├── current.log
       │  │  │  │        ├── previous.insecure.log
       │  │  │  │        └── previous.log
       │  │  │  └── cluster-logging-operator-74dd5994f-6ttgt.yaml
       │  │  ├── cluster-logging-operator-registry-6df49d7d4-mxxff
       │  │  │  ├── cluster-logging-operator-registry
       │  │  │  │  └── cluster-logging-operator-registry
       │  │  │  │     └── logs
       │  │  │  │        ├── current.log
       │  │  │  │        ├── previous.insecure.log
       │  │  │  │        └── previous.log
       │  │  │  ├── cluster-logging-operator-registry-6df49d7d4-mxxff.yaml
       │  │  │  └── mutate-csv-and-generate-sqlite-db
       │  │  │     └── mutate-csv-and-generate-sqlite-db
       │  │  │        └── logs
       │  │  │           ├── current.log
       │  │  │           ├── previous.insecure.log
       │  │  │           └── previous.log
       │  │  ├── curator-1596028500-zkz4s
       │  │  ├── elasticsearch-cdm-lp8l38m0-1-794d6dd989-4jxms
       │  │  ├── elasticsearch-delete-app-1596030300-bpgcx
       │  │  │  ├── elasticsearch-delete-app-1596030300-bpgcx.yaml
       │  │  │  └── indexmanagement
       │  │  │     └── indexmanagement
       │  │  │        └── logs
       │  │  │           ├── current.log
       │  │  │           ├── previous.insecure.log
       │  │  │           └── previous.log
       │  │  ├── fluentd-2tr64
       │  │  │  ├── fluentd
       │  │  │  │  └── fluentd
       │  │  │  │     └── logs
       │  │  │  │        ├── current.log
       │  │  │  │        ├── previous.insecure.log
       │  │  │  │        └── previous.log
       │  │  │  ├── fluentd-2tr64.yaml
       │  │  │  └── fluentd-init
       │  │  │     └── fluentd-init
       │  │  │        └── logs
       │  │  │           ├── current.log
       │  │  │           ├── previous.insecure.log
       │  │  │           └── previous.log
       │  │  ├── kibana-9d69668d4-2rkvz
       │  │  │  ├── kibana
       │  │  │  │  └── kibana
       │  │  │  │     └── logs
       │  │  │  │        ├── current.log
       │  │  │  │        ├── previous.insecure.log
       │  │  │  │        └── previous.log
       │  │  │  ├── kibana-9d69668d4-2rkvz.yaml
       │  │  │  └── kibana-proxy
       │  │  │     └── kibana-proxy
       │  │  │        └── logs
       │  │  │           ├── current.log
       │  │  │           ├── previous.insecure.log
       │  │  │           └── previous.log
       │  └── route.openshift.io
       │     └── routes.yaml
       └── openshift-operators-redhat
          ├── ...
  3. Create a compressed file from the must-gather directory that was just created in your working directory. For example, on a computer that uses a Linux operating system, run the following command:

    $ tar cvaf must-gather.tar.gz must-gather.local.5421342344627712289/ 1
    1
    Make sure to replace must-gather-local.5421342344627712289/ with the actual directory name.
  4. Attach the compressed file to your support case on the Red Hat Customer Portal.

3.4. Obtaining your cluster ID

When providing information to Red Hat Support, it is helpful to provide the unique identifier for your cluster. You can have your cluster ID autofilled by using the OpenShift Container Platform web console. You can also manually obtain your cluster ID by using the web console or the OpenShift CLI (oc).

Prerequisites

  • Access to the cluster as a user with the cluster-admin role.
  • Access to the web console or the OpenShift CLI (oc) installed.

Procedure

  • To open a support case and have your cluster ID autofilled using the web console:

    1. From the toolbar, navigate to (?) HelpOpen Support Case.
    2. The Cluster ID value is autofilled.
  • To manually obtain your cluster ID using the web console:

    1. Navigate to HomeDashboardsOverview.
    2. The value is available in the Cluster ID field of the Details section.
  • To obtain your cluster ID using the OpenShift CLI (oc), run the following command:

    $ oc get clusterversion -o jsonpath='{.items[].spec.clusterID}{"\n"}'

3.5. About sosreport

sosreport is a tool that collects configuration details, system information, and diagnostic data from Red Hat Enterprise Linux (RHEL) and Red Hat Enterprise Linux CoreOS (RHCOS) systems. sosreport provides a standardized way to collect diagnostic information relating to a node, which can then be provided to Red Hat Support for issue diagnosis.

In some support interactions, Red Hat Support may ask you to collect a sosreport archive for a specific OpenShift Container Platform node. For example, it might sometimes be necessary to review system logs or other node-specific data that is not included within the output of oc adm must-gather.

3.6. Generating a sosreport archive for an OpenShift Container Platform cluster node

The recommended way to generate a sosreport for an OpenShift Container Platform 4.6 cluster node is through a debug pod.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have SSH access to your hosts.
  • You have installed the OpenShift CLI (oc).
  • You have a Red Hat standard or premium Subscription.
  • You have a Red Hat Customer Portal account.
  • You have an existing Red Hat Support case ID.

Procedure

  1. Obtain a list of cluster nodes:

    $ oc get nodes
  2. Enter into a debug session on the target node. This step instantiates a debug pod called <node_name>-debug:

    $ oc debug node/my-cluster-node
  3. Set /host as the root directory within the debug shell. The debug pod mounts the host’s root file system in /host within the pod. By changing the root directory to /host, you can run binaries contained in the host’s executable paths:

    # chroot /host
    Note

    OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain> instead.

  4. Start a toolbox container, which includes the required binaries and plug-ins to run sosreport:

    # toolbox
    Note

    If an existing toolbox pod is already running, the toolbox command outputs 'toolbox-' already exists. Trying to start…​. Remove the running toolbox container with podman rm toolbox- and spawn a new toolbox container, to avoid issues with sosreport plug-ins.

  5. Collect a sosreport archive.

    1. Run the sosreport command and enable the crio.all and crio.logs CRI-O container engine sosreport plug-ins:

      # sosreport -k crio.all=on -k crio.logs=on 1
      1
      -k enables you to define sosreport plug-in parameters outside of the defaults.
    2. Press Enter when prompted, to continue.
    3. Provide the Red Hat Support case ID. sosreport adds the ID to the archive’s file name.
    4. The sosreport output provides the archive’s location and checksum. The following sample output references support case ID 01234567:

      Your sosreport has been generated and saved in:
        /host/var/tmp/sosreport-my-cluster-node-01234567-2020-05-28-eyjknxt.tar.xz 1
      
      The checksum is: 382ffc167510fd71b4f12a4f40b97a4e
      1
      The sosreport archive’s file path is outside of the chroot environment because the toolbox container mounts the host’s root directory at /host.
  6. Provide the sosreport archive to Red Hat Support for analysis, using one of the following methods.

    • Upload the file to an existing Red Hat support case directly from an OpenShift Container Platform cluster.

      1. From within the toolbox container, run redhat-support-tool to attach the archive directly to an existing Red Hat support case. This example uses support case ID 01234567:

        # redhat-support-tool addattachment -c 01234567 /host/var/tmp/my-sosreport.tar.xz 1
        1
        The toolbox container mounts the host’s root directory at /host. Reference the absolute path from the toolbox container’s root directory, including /host/, when specifying files to upload through the redhat-support-tool command.
    • Upload the file to an existing Red Hat support case.

      1. Concatenate the sosreport archive by running the oc debug node/<node_name> command and redirect the output to a file. This command assumes you have exited the previous oc debug session:

        $ oc debug node/my-cluster-node -- bash -c 'cat /host/var/tmp/sosreport-my-cluster-node-01234567-2020-05-28-eyjknxt.tar.xz' > /tmp/sosreport-my-cluster-node-01234567-2020-05-28-eyjknxt.tar.xz 1
        1
        The debug container mounts the host’s root directory at /host. Reference the absolute path from the debug container’s root directory, including /host, when specifying target files for concatenation.
        Note

        OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Transferring a sosreport archive from a cluster node by using scp is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to copy a sosreport archive from a node by running scp core@<node>.<cluster_name>.<base_domain>:<file_path> <local_path>.

      2. Navigate to an existing support case within https://access.redhat.com/support/cases/.
      3. Select Attach files and follow the prompts to upload the file.

3.7. Querying bootstrap node journal logs

If you experience bootstrap-related issues, you can gather bootkube.service journald unit logs and container logs from the bootstrap node.

Prerequisites

  • You have SSH access to your bootstrap node.
  • You have the fully qualified domain name of the bootstrap node.

Procedure

  1. Query bootkube.service journald unit logs from a bootstrap node during OpenShift Container Platform installation. Replace <bootstrap_fqdn> with the bootstrap node’s fully qualified domain name:

    $ ssh core@<bootstrap_fqdn> journalctl -b -f -u bootkube.service
    Note

    The bootkube.service log on the bootstrap node outputs etcd connection refused errors, indicating that the bootstrap server is unable to connect to etcd on master nodes. After etcd has started on each master node and the nodes have joined the cluster, the errors should stop.

  2. Collect logs from the bootstrap node containers using podman on the bootstrap node. Replace <bootstrap_fqdn> with the bootstrap node’s fully qualified domain name:

    $ ssh core@<bootstrap_fqdn> 'for pod in $(sudo podman ps -a -q); do sudo podman logs $pod; done'

3.8. Querying cluster node journal logs

You can gather journald unit logs and other logs within /var/log on individual cluster nodes.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).
  • You have SSH access to your hosts.

Procedure

  1. Query kubelet journald unit logs from OpenShift Container Platform cluster nodes. The following example queries master nodes only:

    $ oc adm node-logs --role=master -u kubelet  1
    1
    Replace kubelet as appropriate to query other unit logs.
  2. Collect logs from specific subdirectories under /var/log/ on cluster nodes.

    1. Retrieve a list of logs contained within a /var/log/ subdirectory. The following example lists files in /var/log/openshift-apiserver/ on all master nodes:

      $ oc adm node-logs --role=master --path=openshift-apiserver
    2. Inspect a specific log within a /var/log/ subdirectory. The following example outputs /var/log/openshift-apiserver/audit.log contents from all master nodes:

      $ oc adm node-logs --role=master --path=openshift-apiserver/audit.log
    3. If the API is not functional, review the logs on each node using SSH instead. The following example tails /var/log/openshift-apiserver/audit.log:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo tail -f /var/log/openshift-apiserver/audit.log
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

3.9. Collecting a network trace from an OpenShift Container Platform node or container

When investigating potential network-related OpenShift Container Platform issues, Red Hat Support might request a network packet trace from a specific OpenShift Container Platform cluster node or from a specific container. The recommended method to capture a network trace in OpenShift Container Platform is through a debug pod.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have a Red Hat standard or premium Subscription.
  • You have a Red Hat Customer Portal account.
  • You have an existing Red Hat Support case ID.
  • You have SSH access to your hosts.

Procedure

  1. Obtain a list of cluster nodes:

    $ oc get nodes
  2. Enter into a debug session on the target node. This step instantiates a debug pod called <node_name>-debug:

    $ oc debug node/my-cluster-node
  3. Set /host as the root directory within the debug shell. The debug pod mounts the host’s root file system in /host within the pod. By changing the root directory to /host, you can run binaries contained in the host’s executable paths:

    # chroot /host
    Note

    OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain> instead.

  4. From within the chroot environment console, obtain the node’s interface names:

    # ip ad
  5. Start a toolbox container, which includes the required binaries and plug-ins to run sosreport:

    # toolbox
    Note

    If an existing toolbox pod is already running, the toolbox command outputs 'toolbox-' already exists. Trying to start…​. To avoid tcpdump issues, remove the running toolbox container with podman rm toolbox- and spawn a new toolbox container.

  6. Initiate a tcpdump session on the cluster node and redirect output to a capture file. This example uses ens5 as the interface name:

    $ tcpdump -nn -s 0 -i ens5 -w /host/var/tmp/my-cluster-node_$(date +%d_%m_%Y-%H_%M_%S-%Z).pcap  1
    1
    The tcpdump capture file’s path is outside of the chroot environment because the toolbox container mounts the host’s root directory at /host.
  7. If a tcpdump capture is required for a specific container on the node, follow these steps.

    1. Determine the target container ID. The chroot host command precedes the crictl command in this step because the toolbox container mounts the host’s root directory at /host:

      # chroot /host crictl ps
    2. Determine the container’s process ID. In this example, the container ID is a7fe32346b120:

      # chroot /host crictl inspect --output yaml a7fe32346b120 | grep 'pid' | awk '{print $2}'
    3. Initiate a tcpdump session on the container and redirect output to a capture file. This example uses 49628 as the container’s process ID and ens5 as the interface name. The nsenter command enters the namespace of a target process and runs a command in its namespace. because the target process in this example is a container’s process ID, the tcpdump command is run in the container’s namespace from the host:

      # nsenter -n -t 49628 -- tcpdump -nn -i ens5 -w /host/var/tmp/my-cluster-node-my-container_$(date +%d_%m_%Y-%H_%M_%S-%Z).pcap.pcap  1
      1
      The tcpdump capture file’s path is outside of the chroot environment because the toolbox container mounts the host’s root directory at /host.
  8. Provide the tcpdump capture file to Red Hat Support for analysis, using one of the following methods.

    • Upload the file to an existing Red Hat support case directly from an OpenShift Container Platform cluster.

      1. From within the toolbox container, run redhat-support-tool to attach the file directly to an existing Red Hat Support case. This example uses support case ID 01234567:

        # redhat-support-tool addattachment -c 01234567 /host/var/tmp/my-tcpdump-capture-file.pcap 1
        1
        The toolbox container mounts the host’s root directory at /host. Reference the absolute path from the toolbox container’s root directory, including /host/, when specifying files to upload through the redhat-support-tool command.
    • Upload the file to an existing Red Hat support case.

      1. Concatenate the sosreport archive by running the oc debug node/<node_name> command and redirect the output to a file. This command assumes you have exited the previous oc debug session:

        $ oc debug node/my-cluster-node -- bash -c 'cat /host/var/tmp/my-tcpdump-capture-file.pcap' > /tmp/my-tcpdump-capture-file.pcap 1
        1
        The debug container mounts the host’s root directory at /host. Reference the absolute path from the debug container’s root directory, including /host, when specifying target files for concatenation.
        Note

        OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Transferring a tcpdump capture file from a cluster node by using scp is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to copy a tcpdump capture file from a node by running scp core@<node>.<cluster_name>.<base_domain>:<file_path> <local_path>.

      2. Navigate to an existing support case within https://access.redhat.com/support/cases/.
      3. Select Attach files and follow the prompts to upload the file.

3.10. Providing diagnostic data to Red Hat Support

When investigating OpenShift Container Platform issues, Red Hat Support might ask you to upload diagnostic data to a support case. Files can be uploaded to a support case through the Red Hat Customer Portal, or from an OpenShift Container Platform cluster directly by using the redhat-support-tool command.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have SSH access to your hosts.
  • You have installed the OpenShift CLI (oc).
  • You have a Red Hat standard or premium Subscription.
  • You have a Red Hat Customer Portal account.
  • You have an existing Red Hat Support case ID.

Procedure

  • Upload diagnostic data to an existing Red Hat support case through the Red Hat Customer Portal.

    1. Concatenate a diagnostic file contained on an OpenShift Container Platform node by using the oc debug node/<node_name> command and redirect the output to a file. The following example copies /host/var/tmp/my-diagnostic-data.tar.gz from a debug container to /var/tmp/my-diagnostic-data.tar.gz:

      $ oc debug node/my-cluster-node -- bash -c 'cat /host/var/tmp/my-diagnostic-data.tar.gz' > /var/tmp/my-diagnostic-data.tar.gz 1
      1
      The debug container mounts the host’s root directory at /host. Reference the absolute path from the debug container’s root directory, including /host, when specifying target files for concatenation.
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Transferring files from a cluster node by using scp is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to copy diagnostic files from a node by running scp core@<node>.<cluster_name>.<base_domain>:<file_path> <local_path>.

    2. Navigate to an existing support case within https://access.redhat.com/support/cases/.
    3. Select Attach files and follow the prompts to upload the file.
  • Upload diagnostic data to an existing Red Hat support case directly from an OpenShift Container Platform cluster.

    1. Obtain a list of cluster nodes:

      $ oc get nodes
    2. Enter into a debug session on the target node. This step instantiates a debug pod called <node_name>-debug:

      $ oc debug node/my-cluster-node
    3. Set /host as the root directory within the debug shell. The debug pod mounts the host’s root file system in /host within the pod. By changing the root directory to /host, you can run binaries contained in the host’s executable paths:

      # chroot /host
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain> instead.

    4. Start a toolbox container, which includes the required binaries to run redhat-support-tool:

      # toolbox
      Note

      If an existing toolbox pod is already running, the toolbox command outputs 'toolbox-' already exists. Trying to start…​. Remove the running toolbox container with podman rm toolbox- and spawn a new toolbox container, to avoid issues.

      1. Run redhat-support-tool to attach a file from the debug pod directly to an existing Red Hat Support case. This example uses support case ID '01234567' and example file path /host/var/tmp/my-diagnostic-data.tar.gz:

        # redhat-support-tool addattachment -c 01234567 /host/var/tmp/my-diagnostic-data.tar.gz 1
        1
        The toolbox container mounts the host’s root directory at /host. Reference the absolute path from the toolbox container’s root directory, including /host/, when specifying files to upload through the redhat-support-tool command.

Chapter 4. Summarizing cluster specifications

4.1. Summarizing cluster specifications through clusterversion

You can obtain a summary of OpenShift Container Platform cluster specifications by querying the clusterversion resource.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Query cluster version, availability, uptime, and general status:

    $ oc get clusterversion
  2. Obtain a detailed summary of cluster specifications, update availability, and update history:

    $ oc describe clusterversion

Chapter 5. Troubleshooting

5.1. Troubleshooting installations

5.1.1. Determining where installation issues occur

When troubleshooting OpenShift Container Platform installation issues, you can monitor installation logs to determine at which stage issues occur. Then, retrieve diagnostic data relevant to that stage.

OpenShift Container Platform installation proceeds through the following stages:

  1. Ignition configuration files are created.
  2. The bootstrap machine boots and starts hosting the remote resources required for the master machines to boot.
  3. The master machines fetch the remote resources from the bootstrap machine and finish booting.
  4. The master machines use the bootstrap machine to form an etcd cluster.
  5. The bootstrap machine starts a temporary Kubernetes control plane using the new etcd cluster.
  6. The temporary control plane schedules the production control plane to the master machines.
  7. The temporary control plane shuts down and passes control to the production control plane.
  8. The bootstrap machine adds OpenShift Container Platform components into the production control plane.
  9. The installation program shuts down the bootstrap machine.
  10. The control plane sets up the worker nodes.
  11. The control plane installs additional services in the form of a set of Operators.
  12. The cluster downloads and configures remaining components needed for the day-to-day operation, including the creation of worker machines in supported environments.

5.1.2. User-provisioned infrastructure installation considerations

The default installation method uses installer-provisioned infrastructure. With installer-provisioned infrastructure clusters, OpenShift Container Platform manages all aspects of the cluster, including the operating system itself. If possible, use this feature to avoid having to provision and maintain the cluster infrastructure.

You can alternatively install OpenShift Container Platform 4.6 on infrastructure that you provide. If you use this installation method, follow user-provisioned infrastructure installation documentation carefully. Additionally, review the following considerations before the installation:

  • Check the Red Hat Enterprise Linux (RHEL) Ecosystem to determine the level of Red Hat Enterprise Linux CoreOS (RHCOS) support provided for your chosen server hardware or virtualization technology.
  • Many virtualization and cloud environments require agents to be installed on guest operating systems. Ensure that these agents are installed as a containerized workload deployed through a daemon set.
  • Install cloud provider integration if you want to enable features such as dynamic storage, on-demand service routing, node host name to Kubernetes host name resolution, and cluster autoscaling.

    Note

    It is not possible to enable cloud provider integration in OpenShift Container Platform environments that mix resources from different cloud providers, or that span multiple physical or virtual platforms. The node life cycle controller will not allow nodes that are external to the existing provider to be added to a cluster, and it is not possible to specify more than one cloud provider integration.

  • A provider-specific Machine API implementation is required if you want to use machine sets or autoscaling to automatically provision OpenShift Container Platform cluster nodes.
  • Check whether your chosen cloud provider offers a method to inject Ignition configuration files into hosts as part of their initial deployment. If they do not, you will need to host Ignition configuration files by using an HTTP server. The steps taken to troubleshoot Ignition configuration file issues will differ depending on which of these two methods is deployed.
  • Storage needs to be manually provisioned if you want to leverage optional framework components such as the embedded container registry, ElasticSearch, or Prometheus. Default storage classes are not defined in user-provisioned infrastructure installations unless explicitly configured.
  • A load balancer is required to distribute API requests across all master nodes in highly available OpenShift Container Platform environments. You can use any TCP-based load balancing solution that meets OpenShift Container Platform DNS routing and port requirements.

5.1.3. Checking a load balancer configuration before OpenShift Container Platform installation

Check your load balancer configuration prior to starting an OpenShift Container Platform installation.

Prerequisites

  • You have configured an external load balancer of your choosing, in preparation for an OpenShift Container Platform installation. The following example is based on a Red Hat Enterprise Linux (RHEL) host using HAProxy to provide load balancing services to a cluster.
  • You have configured DNS in preparation for an OpenShift Container Platform installation.
  • You have SSH access to your load balancer.

Procedure

  1. Check that the haproxy systemd service is active:

    $ ssh <user_name>@<load_balancer> systemctl status haproxy
  2. Verify that the load balancer is listening on the required ports. The following example references ports 80, 443, 6443, and 22623.

    • For HAProxy instances running on Red Hat Enterprise Linux (RHEL) 6, verify port status by using the netstat command:

      $ ssh <user_name>@<load_balancer> netstat -nltupe | grep -E ':80|:443|:6443|:22623'
    • For HAProxy instances running on Red Hat Enterprise Linux (RHEL) 7 or 8, verify port status by using the ss command:

      $ ssh <user_name>@<load_balancer> ss -nltupe | grep -E ':80|:443|:6443|:22623'
      Note

      Red Hat recommends the ss command instead of netstat in Red Hat Enterprise Linux (RHEL) 7 or later. ss is provided by the iproute package. For more information on the ss command, see the Red Hat Enterprise Linux (RHEL) 7 Performance Tuning Guide.

  3. Check that the wildcard DNS record resolves to the load balancer:

    $ dig <wildcard_fqdn> @<dns_server>

5.1.4. Specifying OpenShift Container Platform installer log levels

By default, the OpenShift Container Platform installer log level is set to info. If more detailed logging is required when diagnosing a failed OpenShift Container Platform installation, you can increase the openshift-install log level to debug when starting the installation again.

Prerequisites

  • You have access to the installation host.

Procedure

  • Set the installation log level to debug when initiating the installation:

    $ ./openshift-install --dir=<installation_directory> wait-for bootstrap-complete --log-level=debug  1
    1
    Possible log levels include info, warn, error, and debug.

5.1.5. Troubleshooting openshift-install command issues

If you experience issues running the openshift-install command, check the following:

  • The installation has been initiated within 24 hours of Ignition configuration file creation. The Ignition files are created when the following command is run:

    $ ./openshift-install create ignition-configs --dir=./install_dir
  • The install-config.yaml file is in the same directory as the installer. If an alternative installation path is declared by using the ./openshift-install --dir option, verify that the install-config.yaml file exists within that directory.

5.1.6. Monitoring installation progress

You can monitor high-level installation, bootstrap, and control plane logs as an OpenShift Container Platform installation progresses. This provides greater visibility into how an installation progresses and helps identify the stage at which an installation failure occurs.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have SSH access to your hosts.
  • You have the fully qualified domain names of the bootstrap and master nodes.

    Note

    The initial kubeadmin password can be found in <install_directory>/auth/kubeadmin-password on the installation host.

Procedure

  1. Watch the installation log as the installation progresses:

    $ tail -f ~/<installation_directory>/.openshift_install.log
  2. Monitor the bootkube.service journald unit log on the bootstrap node, after it has booted. This provides visibility into the bootstrapping of the first control plane. Replace <bootstrap_fqdn> with the bootstrap node’s fully qualified domain name:

    $ ssh core@<bootstrap_fqdn> journalctl -b -f -u bootkube.service
    Note

    The bootkube.service log on the bootstrap node outputs etcd connection refused errors, indicating that the bootstrap server is unable to connect to etcd on master nodes. After etcd has started on each master node and the nodes have joined the cluster, the errors should stop.

  3. Monitor kubelet.service journald unit logs on master nodes, after they have booted. This provides visibility into master node agent activity.

    1. Monitor the logs using oc:

      $ oc adm node-logs --role=master -u kubelet
    2. If the API is not functional, review the logs using SSH instead. Replace <master-node>.<cluster_name>.<base_domain> with appropriate values:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> journalctl -b -f -u kubelet.service
  4. Monitor crio.service journald unit logs on master nodes, after they have booted. This provides visibility into master node CRI-O container runtime activity.

    1. Monitor the logs using oc:

      $ oc adm node-logs --role=master -u crio
    2. If the API is not functional, review the logs using SSH instead. Replace <master-node>.<cluster_name>.<base_domain> with appropriate values:

      $ ssh core@master-N.cluster_name.sub_domain.domain journalctl -b -f -u crio.service

5.1.7. Gathering bootstrap node diagnostic data

When experiencing bootstrap-related issues, you can gather bootkube.service journald unit logs and container logs from the bootstrap node.

Prerequisites

  • You have SSH access to your bootstrap node.
  • You have the fully qualified domain name of the bootstrap node.
  • If you are hosting Ignition configuration files by using an HTTP server, you must have the HTTP server’s fully qualified domain name and the port number. You must also have SSH access to the HTTP host.

Procedure

  1. If you have access to the bootstrap node’s console, monitor the console until the node reaches the login prompt.
  2. Verify the Ignition file configuration.

    • If you are hosting Ignition configuration files by using an HTTP server.

      1. Verify the bootstrap node Ignition file URL. Replace <http_server_fqdn> with HTTP server’s fully qualified domain name:

        $ curl -I http://<http_server_fqdn>:<port>/bootstrap.ign  1
        1
        The -I option returns the header only. If the Ignition file is available on the specified URL, the command returns 200 OK status. If it is not available, the command returns 404 file not found.
      2. To verify that the Ignition file was received by the bootstrap node, query the HTTP server logs on the serving host. For example, if you are using an Apache web server to serve Ignition files, enter the following command:

        $ grep -is 'bootstrap.ign' /var/log/httpd/access_log

        If the bootstrap Ignition file is received, the associated HTTP GET log message will include a 200 OK success status, indicating that the request succeeded.

      3. If the Ignition file was not received, check that the Ignition files exist and that they have the appropriate file and web server permissions on the serving host directly.
    • If you are using a cloud provider mechanism to inject Ignition configuration files into hosts as part of their initial deployment.

      1. Review the bootstrap node’s console to determine if the mechanism is injecting the bootstrap node Ignition file correctly.
  3. Verify the availability of the bootstrap node’s assigned storage device.
  4. Verify that the bootstrap node has been assigned an IP address from the DHCP server.
  5. Collect bootkube.service journald unit logs from the bootstrap node. Replace <bootstrap_fqdn> with the bootstrap node’s fully qualified domain name:

    $ ssh core@<bootstrap_fqdn> journalctl -b -f -u bootkube.service
    Note

    The bootkube.service log on the bootstrap node outputs etcd connection refused errors, indicating that the bootstrap server is unable to connect to etcd on master nodes. After etcd has started on each master node and the nodes have joined the cluster, the errors should stop.

  6. Collect logs from the bootstrap node containers.

    1. Collect the logs using podman on the bootstrap node. Replace <bootstrap_fqdn> with the bootstrap node’s fully qualified domain name:

      $ ssh core@<bootstrap_fqdn> 'for pod in $(sudo podman ps -a -q); do sudo podman logs $pod; done'
  7. If the bootstrap process fails, verify the following.

    • You can resolve api.<cluster_name>.<base_domain> from the installation host.
    • The load balancer proxies port 6443 connections to bootstrap and master nodes. Ensure that the proxy configuration meets OpenShift Container Platform installation requirements.

5.1.8. Investigating master node installation issues

If you experience master node installation issues, determine the master node, OpenShift Container Platform software defined network (SDN), and network Operator status. Collect kubelet.service, crio.service journald unit logs, and master node container logs for visibility into master node agent, CRI-O container runtime, and pod activity.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have SSH access to your hosts.
  • You have the fully qualified domain names of the bootstrap and master nodes.
  • If you are hosting Ignition configuration files by using an HTTP server, you must have the HTTP server’s fully qualified domain name and the port number. You must also have SSH access to the HTTP host.

    Note

    The initial kubeadmin password can be found in <install_directory>/auth/kubeadmin-password on the installation host.

Procedure

  1. If you have access to the master node’s console, monitor the console until the node reaches the login prompt. During the installation, Ignition log messages are output to the console.
  2. Verify Ignition file configuration.

    • If you are hosting Ignition configuration files by using an HTTP server.

      1. Verify the master node Ignition file URL. Replace <http_server_fqdn> with HTTP server’s fully qualified domain name:

        $ curl -I http://<http_server_fqdn>:<port>/master.ign  1
        1
        The -I option returns the header only. If the Ignition file is available on the specified URL, the command returns 200 OK status. If it is not available, the command returns 404 file not found.
      2. To verify that the Ignition file was received by the master node, query the HTTP server logs on the serving host. For example, if you are using an Apache web server to serve Ignition files:

        $ grep -is 'master.ign' /var/log/httpd/access_log

        If the master Ignition file is received, the associated HTTP GET log message will include a 200 OK success status, indicating that the request succeeded.

      3. If the Ignition file was not received, check that it exists on the serving host directly. Ensure that the appropriate file and web server permissions are in place.
    • If you are using a cloud provider mechanism to inject Ignition configuration files into hosts as part of their initial deployment.

      1. Review the master node’s console to determine if the mechanism is injecting the master node Ignition file correctly.
  3. Check the availability of the master node’s assigned storage device.
  4. Verify that the master node has been assigned an IP address from the DHCP server.
  5. Determine master node status.

    1. Query master node status:

      $ oc get nodes
    2. If one of the master nodes does not reach a Ready status, retrieve a detailed node description:

      $ oc describe node <master_node>
      Note

      It is not possible to run oc commands if an installation issue prevents the OpenShift Container Platform API from running or if the kubelet is not running yet on each node:

  6. Determine OpenShift Container Platform SDN status.

    1. Review sdn-controller, sdn, and ovs daemon set status, in the openshift-sdn namespace:

      $ oc get daemonsets -n openshift-sdn
    2. If those resources are listed as Not found, review pods in the openshift-sdn namespace:

      $ oc get pods -n openshift-sdn
    3. Review logs relating to failed OpenShift Container Platform SDN pods in the openshift-sdn namespace:

      $ oc logs <sdn_pod> -n openshift-sdn
  7. Determine cluster network configuration status.

    1. Review whether the cluster’s network configuration exists:

      $ oc get network.config.openshift.io cluster -o yaml
    2. If the installer failed to create the network configuration, generate the Kubernetes manifests again and review message output:

      $ ./openshift-install create manifests
    3. Review the pod status in the openshift-network-operator namespace to determine whether the Cluster Network Operator (CNO) is running:

      $ oc get pods -n openshift-network-operator
    4. Gather network Operator pod logs from the openshift-network-operator namespace:

      $ oc logs pod/<network_operator_pod_name> -n openshift-network-operator
  8. Monitor kubelet.service journald unit logs on master nodes, after they have booted. This provides visibility into master node agent activity.

    1. Retrieve the logs using oc:

      $ oc adm node-logs --role=master -u kubelet
    2. If the API is not functional, review the logs using SSH instead. Replace <master-node>.<cluster_name>.<base_domain> with appropriate values:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> journalctl -b -f -u kubelet.service
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

  9. Retrieve crio.service journald unit logs on master nodes, after they have booted. This provides visibility into master node CRI-O container runtime activity.

    1. Retrieve the logs using oc:

      $ oc adm node-logs --role=master -u crio
    2. If the API is not functional, review the logs using SSH instead:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> journalctl -b -f -u crio.service
  10. Collect logs from specific subdirectories under /var/log/ on master nodes.

    1. Retrieve a list of logs contained within a /var/log/ subdirectory. The following example lists files in /var/log/openshift-apiserver/ on all master nodes:

      $ oc adm node-logs --role=master --path=openshift-apiserver
    2. Inspect a specific log within a /var/log/ subdirectory. The following example outputs /var/log/openshift-apiserver/audit.log contents from all master nodes:

      $ oc adm node-logs --role=master --path=openshift-apiserver/audit.log
    3. If the API is not functional, review the logs on each node using SSH instead. The following example tails /var/log/openshift-apiserver/audit.log:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo tail -f /var/log/openshift-apiserver/audit.log
  11. Review master node container logs using SSH.

    1. List the containers:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl ps -a
    2. Retrieve a container’s logs using crictl:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl logs -f <container_id>
  12. If you experience master node configuration issues, verify that the MCO, MCO endpoint, and DNS record are functioning. The Machine Config Operator (MCO) manages operating system configuration during the installation procedure. Also verify system clock accuracy and certificate validity.

    1. Test whether the MCO endpoint is available. Replace <cluster_name> with appropriate values:

      $ curl https://api-int.<cluster_name>:22623/config/master
    2. If the endpoint is unresponsive, verify load balancer configuration. Ensure that the endpoint is configured to run on port 22623.
    3. Verify that the MCO endpoint’s DNS record is configured and resolves to the load balancer.

      1. Run a DNS lookup for the defined MCO endpoint name:

        $ dig api-int.<cluster_name> @<dns_server>
      2. Run a reverse lookup to the assigned MCO IP address on the load balancer:

        $ dig -x <load_balancer_mco_ip_address> @<dns_server>
    4. Verify that the MCO is functioning from the bootstrap node directly. Replace <bootstrap_fqdn> with the bootstrap node’s fully qualified domain name:

      $ ssh core@<bootstrap_fqdn> curl https://api-int.<cluster_name>:22623/config/master
    5. System clock time must be synchronized between bootstrap, master, and worker nodes. Check each node’s system clock reference time and time synchronization statistics:

      $ ssh core@<node>.<cluster_name>.<base_domain> chronyc tracking
    6. Review certificate validity:

      $ openssl s_client -connect api-int.<cluster_name>:22623 | openssl x509 -noout -text

5.1.9. Investigating etcd installation issues

If you experience etcd issues during installation, you can check etcd pod status and collect etcd pod logs. You can also verify etcd DNS records and check DNS availability on master nodes.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have SSH access to your hosts.
  • You have the fully qualified domain names of the master nodes.

Procedure

  1. Check the status of etcd pods.

    1. Review the status of pods in the openshift-etcd namespace:

      $ oc get pods -n openshift-etcd
    2. Review the status of pods in the openshift-etcd-operator namespace:

      $ oc get pods -n openshift-etcd-operator
  2. If any of the pods listed by the previous commands are not showing a Running or a Completed status, gather diagnostic information for the pod.

    1. Review events for the pod:

      $ oc describe pod/<pod_name> -n <namespace>
    2. Inspect the pod’s logs:

      $ oc logs pod/<pod_name> -n <namespace>
    3. If the pod has more than one container, the preceding command will create an error, and the container names will be provided in the error message. Inspect logs for each container:

      $ oc logs pod/<pod_name> -c <container_name> -n <namespace>
  3. If the API is not functional, review etcd pod and container logs on each master node by using SSH instead. Replace <master-node>.<cluster_name>.<base_domain> with appropriate values.

    1. List etcd pods on each master node:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl pods --name=etcd-
    2. For any pods not showing Ready status, inspect pod status in detail. Replace <pod_id> with the pod’s ID listed in the output of the preceding command:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl inspectp <pod_id>
    3. List containers related to a pod:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl ps | grep '<pod_id>'
    4. For any containers not showing Ready status, inspect container status in detail. Replace <container_id> with container IDs listed in the output of the preceding command:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl inspect <container_id>
    5. Review the logs for any containers not showing a Ready status. Replace <container_id> with the container IDs listed in the output of the preceding command:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl logs -f <container_id>
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

  4. Validate primary and secondary DNS server connectivity from master nodes.

5.1.10. Investigating master node kubelet and API server issues

To investigate master node kubelet and API server issues during installation, check DNS, DHCP, and load balancer functionality. Also, verify that certificates have not expired.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have SSH access to your hosts.
  • You have the fully qualified domain names of the master nodes.

Procedure

  1. Verify that the API server’s DNS record directs the kubelet on master nodes to https://api-int.<cluster_name>.<base_domain>:6443. Ensure that the record references the load balancer.
  2. Ensure that the load balancer’s port 6443 definition references each master node.
  3. Check that unique master node host names have been provided by DHCP.
  4. Inspect the kubelet.service journald unit logs on each master node.

    1. Retrieve the logs using oc:

      $ oc adm node-logs --role=master -u kubelet
    2. If the API is not functional, review the logs using SSH instead. Replace <master-node>.<cluster_name>.<base_domain> with appropriate values:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> journalctl -b -f -u kubelet.service
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

  5. Check for certificate expiration messages in the master node kubelet logs.

    1. Retrieve the log using oc:

      $ oc adm node-logs --role=master -u kubelet | grep -is 'x509: certificate has expired'
    2. If the API is not functional, review the logs using SSH instead. Replace <master-node>.<cluster_name>.<base_domain> with appropriate values:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> journalctl -b -f -u kubelet.service  | grep -is 'x509: certificate has expired'

5.1.11. Investigating worker node installation issues

If you experience worker node installation issues, you can review the worker node status. Collect kubelet.service, crio.service journald unit logs and the worker node container logs for visibility into the worker node agent, CRI-O container runtime and pod activity. Additionally, you can check the Ignition file and Machine API Operator functionality. If worker node post-installation configuration fails, check Machine Config Operator (MCO) and DNS functionality. You can also verify system clock synchronization between the bootstrap, master, and worker nodes, and validate certificates.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have SSH access to your hosts.
  • You have the fully qualified domain names of the bootstrap and worker nodes.
  • If you are hosting Ignition configuration files by using an HTTP server, you must have the HTTP server’s fully qualified domain name and the port number. You must also have SSH access to the HTTP host.

    Note

    The initial kubeadmin password can be found in <install_directory>/auth/kubeadmin-password on the installation host.

Procedure

  1. If you have access to the worker node’s console, monitor the console until the node reaches the login prompt. During the installation, Ignition log messages are output to the console.
  2. Verify Ignition file configuration.

    • If you are hosting Ignition configuration files by using an HTTP server.

      1. Verify the worker node Ignition file URL. Replace <http_server_fqdn> with HTTP server’s fully qualified domain name:

        $ curl -I http://<http_server_fqdn>:<port>/worker.ign  1
        1
        The -I option returns the header only. If the Ignition file is available on the specified URL, the command returns 200 OK status. If it is not available, the command returns 404 file not found.
      2. To verify that the Ignition file was received by the worker node, query the HTTP server logs on the HTTP host. For example, if you are using an Apache web server to serve Ignition files:

        $ grep -is 'worker.ign' /var/log/httpd/access_log

        If the worker Ignition file is received, the associated HTTP GET log message will include a 200 OK success status, indicating that the request succeeded.

      3. If the Ignition file was not received, check that it exists on the serving host directly. Ensure that the appropriate file and web server permissions are in place.
    • If you are using a cloud provider mechanism to inject Ignition configuration files into hosts as part of their initial deployment.

      1. Review the worker node’s console to determine if the mechanism is injecting the worker node Ignition file correctly.
  3. Check the availability of the worker node’s assigned storage device.
  4. Verify that the worker node has been assigned an IP address from the DHCP server.
  5. Determine worker node status.

    1. Query node status:

      $ oc get nodes
    2. Retrieve a detailed node description for any worker nodes not showing a Ready status:

      $ oc describe node <worker_node>
      Note

      It is not possible to run oc commands if an installation issue prevents the OpenShift Container Platform API from running or if the kubelet is not running yet on each node.

  6. Unlike master nodes, worker nodes are deployed and scaled using the Machine API Operator. Check the status of the Machine API Operator.

    1. Review Machine API Operator pod status:

      $ oc get pods -n openshift-machine-api
    2. If the Machine API Operator pod does not have a Ready status, detail the pod’s events:

      $ oc describe pod/<machine_api_operator_pod_name> -n openshift-machine-api
    3. Inspect machine-api-operator container logs. The container runs within the machine-api-operator pod:

      $ oc logs pod/<machine_api_operator_pod_name> -n openshift-machine-api -c machine-api-operator
    4. Also inspect kube-rbac-proxy container logs. The container also runs within the machine-api-operator pod:

      $ oc logs pod/<machine_api_operator_pod_name> -n openshift-machine-api -c kube-rbac-proxy
  7. Monitor kubelet.service journald unit logs on worker nodes, after they have booted. This provides visibility into worker node agent activity.

    1. Retrieve the logs using oc:

      $ oc adm node-logs --role=worker -u kubelet
    2. If the API is not functional, review the logs using SSH instead. Replace <worker-node>.<cluster_name>.<base_domain> with appropriate values:

      $ ssh core@<worker-node>.<cluster_name>.<base_domain> journalctl -b -f -u kubelet.service
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

  8. Retrieve crio.service journald unit logs on worker nodes, after they have booted. This provides visibility into worker node CRI-O container runtime activity.

    1. Retrieve the logs using oc:

      $ oc adm node-logs --role=worker -u crio
    2. If the API is not functional, review the logs using SSH instead:

      $ ssh core@<worker-node>.<cluster_name>.<base_domain> journalctl -b -f -u crio.service
  9. Collect logs from specific subdirectories under /var/log/ on worker nodes.

    1. Retrieve a list of logs contained within a /var/log/ subdirectory. The following example lists files in /var/log/sssd/ on all worker nodes:

      $ oc adm node-logs --role=worker --path=sssd
    2. Inspect a specific log within a /var/log/ subdirectory. The following example outputs /var/log/sssd/audit.log contents from all worker nodes:

      $ oc adm node-logs --role=worker --path=sssd/sssd.log
    3. If the API is not functional, review the logs on each node using SSH instead. The following example tails /var/log/sssd/sssd.log:

      $ ssh core@<worker-node>.<cluster_name>.<base_domain> sudo tail -f /var/log/sssd/sssd.log
  10. Review worker node container logs using SSH.

    1. List the containers:

      $ ssh core@<worker-node>.<cluster_name>.<base_domain> sudo crictl ps -a
    2. Retrieve a container’s logs using crictl:

      $ ssh core@<worker-node>.<cluster_name>.<base_domain> sudo crictl logs -f <container_id>
  11. If you experience worker node configuration issues, verify that the MCO, MCO endpoint, and DNS record are functioning. The Machine Config Operator (MCO) manages operating system configuration during the installation procedure. Also verify system clock accuracy and certificate validity.

    1. Test whether the MCO endpoint is available. Replace <cluster_name> with appropriate values:

      $ curl https://api-int.<cluster_name>:22623/config/worker
    2. If the endpoint is unresponsive, verify load balancer configuration. Ensure that the endpoint is configured to run on port 22623.
    3. Verify that the MCO endpoint’s DNS record is configured and resolves to the load balancer.

      1. Run a DNS lookup for the defined MCO endpoint name:

        $ dig api-int.<cluster_name> @<dns_server>
      2. Run a reverse lookup to the assigned MCO IP address on the load balancer:

        $ dig -x <load_balancer_mco_ip_address> @<dns_server>
    4. Verify that the MCO is functioning from the bootstrap node directly. Replace <bootstrap_fqdn> with the bootstrap node’s fully qualified domain name:

      $ ssh core@<bootstrap_fqdn> curl https://api-int.<cluster_name>:22623/config/worker
    5. System clock time must be synchronized between bootstrap, master, and worker nodes. Check each node’s system clock reference time and time synchronization statistics:

      $ ssh core@<node>.<cluster_name>.<base_domain> chronyc tracking
    6. Review certificate validity:

      $ openssl s_client -connect api-int.<cluster_name>:22623 | openssl x509 -noout -text

5.1.12. Querying Operator status after installation

You can check Operator status at the end of an installation. Retrieve diagnostic data for Operators that do not become available. Review logs for any Operator pods that are listed as Pending or have an error status. Validate base images used by problematic pods.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Check that cluster Operators are all available at the end of an installation.

    $ oc get clusteroperators
  2. Verify that all of the required certificate signing requests (CSRs) are approved. Some nodes might not move to a Ready status and some cluster Operators might not become available if there are pending CSRs.

    1. Check the status of the CSRs and ensure that you see a client and server request with the Pending or Approved status for each machine that you added to the cluster:

      $ oc get csr

      Example output

      NAME        AGE     REQUESTOR                                                                   CONDITION
      csr-8b2br   15m     system:serviceaccount:openshift-machine-config-operator:node-bootstrapper   Pending 1
      csr-8vnps   15m     system:serviceaccount:openshift-machine-config-operator:node-bootstrapper   Pending
      csr-bfd72   5m26s   system:node:ip-10-0-50-126.us-east-2.compute.internal                       Pending 2
      csr-c57lv   5m26s   system:node:ip-10-0-95-157.us-east-2.compute.internal                       Pending
      ...

      1
      A client request CSR.
      2
      A server request CSR.

      In this example, two machines are joining the cluster. You might see more approved CSRs in the list.

    2. If the CSRs were not approved, after all of the pending CSRs for the machines you added are in Pending status, approve the CSRs for your cluster machines:

      Note

      Because the CSRs rotate automatically, approve your CSRs within an hour of adding the machines to the cluster. If you do not approve them within an hour, the certificates will rotate, and more than two certificates will be present for each node. You must approve all of these certificates. After you approve the initial CSRs, the subsequent node client CSRs are automatically approved by the cluster kube-controller-manager.

      Note

      For clusters running on platforms that are not machine API enabled, such as bare metal and other user-provisioned infrastructure, you must implement a method of automatically approving the kubelet serving certificate requests (CSRs). If a request is not approved, then the oc exec, oc rsh, and oc logs commands cannot succeed, because a serving certificate is required when the API server connects to the kubelet. Any operation that contacts the Kubelet endpoint requires this certificate approval to be in place. The method must watch for new CSRs, confirm that the CSR was submitted by the node-bootstrapper service account in the system:node or system:admin groups, and confirm the identity of the node.

      • To approve them individually, run the following command for each valid CSR:

        $ oc adm certificate approve <csr_name> 1
        1
        <csr_name> is the name of a CSR from the list of current CSRs.
      • To approve all pending CSRs, run the following command:

        $ oc get csr -o go-template='{{range .items}}{{if not .status}}{{.metadata.name}}{{"\n"}}{{end}}{{end}}' | xargs oc adm certificate approve
  3. View Operator events:

    $ oc describe clusteroperator <operator_name>
  4. Review Operator pod status within the Operator’s namespace:

    $ oc get pods -n <operator_namespace>
  5. Obtain a detailed description for pods that do not have Running status:

    $ oc describe pod/<operator_pod_name> -n <operator_namespace>
  6. Inspect pod logs:

    $ oc logs pod/<operator_pod_name> -n <operator_namespace>
  7. When experiencing pod base image related issues, review base image status.

    1. Obtain details of the base image used by a problematic pod:

      $ oc get pod -o "jsonpath={range .status.containerStatuses[*]}{.name}{'\t'}{.state}{'\t'}{.image}{'\n'}{end}" <operator_pod_name> -n <operator_namespace>
    2. List base image release information:

      $ oc adm release info <image_path>:<tag> --commits

5.1.13. Gathering logs from a failed installation

If you gave an SSH key to your installation program, you can gather data about your failed installation.

Note

You use a different command to gather logs about an unsuccessful installation than to gather logs from a running cluster. If you must gather logs from a running cluster, use the oc adm must-gather command.

Prerequisites

  • Your OpenShift Container Platform installation failed before the bootstrap process finished. The bootstrap node is running and accessible through SSH.
  • The ssh-agent process is active on your computer, and you provided the same SSH key to both the ssh-agent process and the installation program.
  • If you tried to install a cluster on infrastructure that you provisioned, you must have the fully qualified domain names of the bootstrap and master nodes.

Procedure

  1. Generate the commands that are required to obtain the installation logs from the bootstrap and control plane machines:

    • If you used installer-provisioned infrastructure, change to the directory that contains the installation program and run the following command:

      $ ./openshift-install gather bootstrap --dir=<installation_directory> 1
      1
      installation_directory is the directory you specified when you ran ./openshift-install create cluster. This directory contains the OpenShift Container Platform definition files that the installation program creates.

      For installer-provisioned infrastructure, the installation program stores information about the cluster, so you do not specify the host names or IP addresses.

    • If you used infrastructure that you provisioned yourself, change to the directory that contains the installation program and run the following command:

      $ ./openshift-install gather bootstrap --dir=<installation_directory> \ 1
          --bootstrap <bootstrap_address> \ 2
          --master <master_1_address> \ 3
          --master <master_2_address> \ 4
          --master <master_3_address>" 5
      1
      For installation_directory, specify the same directory you specified when you ran ./openshift-install create cluster. This directory contains the OpenShift Container Platform definition files that the installation program creates.
      2
      <bootstrap_address> is the fully qualified domain name or IP address of the cluster’s bootstrap machine.
      3 4 5
      For each control plane, or master, machine in your cluster, replace <master_*_address> with its fully qualified domain name or IP address.
      Note

      A default cluster contains three control plane machines. List all of your control plane machines as shown, no matter how many your cluster uses.

    Example output

    INFO Pulling debug logs from the bootstrap machine
    INFO Bootstrap gather logs captured here "<installation_directory>/log-bundle-<timestamp>.tar.gz"

    If you open a Red Hat support case about your installation failure, include the compressed logs in the case.

5.1.14. Additional resources

  • See Installation process for more details on OpenShift Container Platform installation types and process.

5.2. Verifying node health

5.2.1. Reviewing node status, resource usage, and configuration

Review cluster node health status, resource consumption statistics, and node logs. Additionally, query kubelet status on individual nodes.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. List the name, status, and role for all nodes in the cluster:

    $ oc get nodes
  2. Summarize CPU and memory usage for each node within the cluster:

    $ oc adm top nodes
  3. Summarize CPU and memory usage for a specific node:

    $ oc adm top node -l my-node

5.2.2. Querying the kubelet’s status on a node

You can review cluster node health status, resource consumption statistics, and node logs. Additionally, you can query kubelet status on individual nodes.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. The kubelet is managed using a systemd service on each node. Review the kubelet’s status by querying the kubelet systemd service within a debug pod.

    1. Start a debug pod for a node:

      $ oc debug node/my-node
    2. Set /host as the root directory within the debug shell. The debug pod mounts the host’s root file system in /host within the pod. By changing the root directory to /host, you can run binaries contained in the host’s executable paths:

      # chroot /host
      Note

      OpenShift Container Platform cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain> instead.

    3. Check whether the kubelet systemd service is active on the node:

      # systemctl is-active kubelet
    4. Output a more detailed kubelet.service status summary:

      # systemctl status kubelet

5.2.3. Querying cluster node journal logs

You can gather journald unit logs and other logs within /var/log on individual cluster nodes.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).
  • You have SSH access to your hosts.

Procedure

  1. Query kubelet journald unit logs from OpenShift Container Platform cluster nodes. The following example queries master nodes only:

    $ oc adm node-logs --role=master -u kubelet  1
    1
    Replace kubelet as appropriate to query other unit logs.
  2. Collect logs from specific subdirectories under /var/log/ on cluster nodes.

    1. Retrieve a list of logs contained within a /var/log/ subdirectory. The following example lists files in /var/log/openshift-apiserver/ on all master nodes:

      $ oc adm node-logs --role=master --path=openshift-apiserver
    2. Inspect a specific log within a /var/log/ subdirectory. The following example outputs /var/log/openshift-apiserver/audit.log contents from all master nodes:

      $ oc adm node-logs --role=master --path=openshift-apiserver/audit.log
    3. If the API is not functional, review the logs on each node using SSH instead. The following example tails /var/log/openshift-apiserver/audit.log:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo tail -f /var/log/openshift-apiserver/audit.log
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

5.3. Troubleshooting CRI-O container runtime issues

5.3.1. About CRI-O container runtime engine

CRI-O is a Kubernetes-native container runtime implementation that integrates closely with the operating system to deliver an efficient and optimized Kubernetes experience. CRI-O provides facilities for running, stopping, and restarting containers.

The CRI-O container runtime engine is managed using a systemd service on each OpenShift Container Platform cluster node. When container runtime issues occur, verify the status of the crio systemd service on each node. Gather CRI-O journald unit logs from nodes that manifest container runtime issues.

5.3.2. Verifying CRI-O runtime engine status

You can verify CRI-O container runtime engine status on each cluster node.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Review CRI-O status by querying the crio systemd service on a node, within a debug pod.

    1. Start a debug pod for a node:

      $ oc debug node/my-node
    2. Set /host as the root directory within the debug shell. The debug pod mounts the host’s root file system in /host within the pod. By changing the root directory to /host, you can run binaries contained in the host’s executable paths:

      # chroot /host
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain> instead.

    3. Check whether the crio systemd service is active on the node:

      # systemctl is-active crio
    4. Output a more detailed kubelet.service status summary:

      # systemctl status crio

5.3.3. Gathering CRI-O journald unit logs

If you experience CRI-O issues, you can obtain CRI-O journald unit logs from a node.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).
  • You have the fully qualified domain names of the control plane, or master machines.

Procedure

  1. Gather CRI-O journald unit logs. The following example collects logs from all master nodes within the cluster:

    $ oc adm node-logs --role=master -u crio
  2. Gather CRI-O journald unit logs from a specific node:

    $ oc adm node-logs <node_name> -u crio
  3. If the API is not functional, review the logs using SSH instead. Replace <node>.<cluster_name>.<base_domain> with appropriate values:

    $ ssh core@<node>.<cluster_name>.<base_domain> journalctl -b -f -u crio.service
    Note

    OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

5.4. Troubleshooting network issues

5.4.1. How the network interface is selected

For installations on bare metal or with virtual machines that have more than one network interface controller (NIC), the NIC that OpenShift Container Platform uses for communication with the Kubernetes API server is determined by the nodeip-configuration.service service unit that is run by systemd when the node boots. The service iterates through the network interfaces on the node and the first network interface that is configured with a subnet than can host the IP address for the API server is selected for OpenShift Container Platform communication.

After the nodeip-configuration.service service determines the correct NIC, the service creates the /etc/systemd/system/kubelet.service.d/20-nodenet.conf file. The 20-nodenet.conf file sets the KUBELET_NODE_IP environment variable to the IP address that the service selected.

When the kubelet service starts, it reads the value of the environment variable from the 20-nodenet.conf file and sets the IP address as the value to the --node-ip kubelet command-line argument. As a result, the kubelet service uses the selected IP address as the node IP address.

If hardware or networking is reconfigured after installation, it is possible that the nodeip-configuration.service service can select a different NIC after a reboot. In some cases, you might be able to detect that a different NIC is selected by reviewing the INTERNAL-IP column in the output from the oc get nodes -o wide command.

If network communication is disrupted or misconfigured because a different NIC is selected, one strategy for overriding the selection process is to set the correct IP address explicitly. The following list identifies the high-level steps and considerations:

  • Create a shell script that determines the IP address to use for OpenShift Container Platform communication. Have the script create a custom unit file such as /etc/systemd/system/kubelet.service.d/98-nodenet-override.conf. Use the custom unit file, 98-nodenet-override.conf, to set the KUBELET_NODE_IP environment variable to the IP address.
  • Do not overwrite the /etc/systemd/system/kubelet.service.d/20-nodenet.conf file. Specify a file name with a numerically higher value such as 98-nodenet-override.conf in the same directory path. The goal is to have the custom unit file run after 20-nodenet.conf and override the value of the environment variable.
  • Create a machine config object with the shell script as a base64-encoded string and use the Machine Config Operator to deploy the script to the nodes at a file system path such as /usr/local/bin/override-node-ip.sh.
  • Ensure that systemctl daemon-reload runs after the shell script runs. The simplest method is to specify ExecStart=systemctl daemon-reload in the machine config, as shown in the following sample.

Sample machine config to override the network interface for kubelet

apiVersion: machineconfiguration.openshift.io/v1
kind: MachineConfig
metadata:
  labels:
     machineconfiguration.openshift.io/role: worker
  name: 98-nodenet-override
spec:
  config:
    ignition:
      version: 3.1.0
    storage:
      files:
      - contents:
          source: data:text/plain;charset=utf-8;base64,<encoded_script>
        mode: 0755
        overwrite: true
        path: /usr/local/bin/override-node-ip.sh
    systemd:
      units:
      - contents: |
          [Unit]
          Description=Override node IP detection
          Wants=network-online.target
          Before=kubelet.service
          After=network-online.target
          [Service]
          Type=oneshot
          ExecStart=/usr/local/bin/override-node-ip.sh
          ExecStart=systemctl daemon-reload
          [Install]
          WantedBy=multi-user.target
        enabled: true
        name: nodenet-override.service

5.5. Troubleshooting Operator issues

Operators are a method of packaging, deploying, and managing an OpenShift Container Platform application. They act like an extension of the software vendor’s engineering team, watching over an OpenShift Container Platform environment and using its current state to make decisions in real time. Operators are designed to handle upgrades seamlessly, react to failures automatically, and not take shortcuts, such as skipping a software backup process to save time.

OpenShift Container Platform 4.6 includes a default set of Operators that are required for proper functioning of the cluster. These default Operators are managed by the Cluster Version Operator (CVO).

As a cluster administrator, you can install application Operators from the OperatorHub using the OpenShift Container Platform web console or the CLI. You can then subscribe the Operator to one or more namespaces to make it available for developers on your cluster. Application Operators are managed by Operator Lifecycle Manager (OLM).

If you experience Operator issues, verify Operator subscription status. Check Operator pod health across the cluster and gather Operator logs for diagnosis.

5.5.1. Operator subscription condition types

Subscriptions can report the following condition types:

Table 5.1. Subscription condition types

ConditionDescription

CatalogSourcesUnhealthy

Some or all of the catalog sources to be used in resolution are unhealthy.

InstallPlanMissing

An install plan for a subscription is missing.

InstallPlanPending

An install plan for a subscription is pending installation.

InstallPlanFailed

An install plan for a subscription has failed.

Note

Default OpenShift Container Platform cluster Operators are managed by the Cluster Version Operator (CVO) and they do not have a Subscription object. Application Operators are managed by Operator Lifecycle Manager (OLM) and they have a Subscription object.

5.5.2. Viewing Operator subscription status using the CLI

You can view Operator subscription status using the CLI.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. List Operator subscriptions:

    $ oc get subs -n <operator_namespace>
  2. Use the oc describe command to inspect a Subscription resource:

    $ oc describe sub <subscription_name> -n <operator_namespace>
  3. In the command output, find the Conditions section for the status of Operator subscription condition types. In the following example, the CatalogSourcesUnhealthy condition type has a status of false because all available catalog sources are healthy:

    Example output

    Conditions:
       Last Transition Time:  2019-07-29T13:42:57Z
       Message:               all available catalogsources are healthy
       Reason:                AllCatalogSourcesHealthy
       Status:                False
       Type:                  CatalogSourcesUnhealthy

Note

Default OpenShift Container Platform cluster Operators are managed by the Cluster Version Operator (CVO) and they do not have a Subscription object. Application Operators are managed by Operator Lifecycle Manager (OLM) and they have a Subscription object.

5.5.3. Querying Operator pod status

You can list Operator pods within a cluster and their status. You can also collect a detailed Operator pod summary.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. List Operators running in the cluster. The output includes Operator version, availability, and up-time information:

    $ oc get clusteroperators
  2. List Operator pods running in the Operator’s namespace, plus pod status, restarts, and age:

    $ oc get pod -n <operator_namespace>
  3. Output a detailed Operator pod summary:

    $ oc describe pod <operator_pod_name> -n <operator_namespace>
  4. If an Operator issue is node-specific, query Operator container status on that node.

    1. Start a debug pod for the node:

      $ oc debug node/my-node
    2. Set /host as the root directory within the debug shell. The debug pod mounts the host’s root file system in /host within the pod. By changing the root directory to /host, you can run binaries contained in the host’s executable paths:

      # chroot /host
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain> instead.

    3. List details about the node’s containers, including state and associated pod IDs:

      # crictl ps
    4. List information about a specific Operator container on the node. The following example lists information about the network-operator container:

      # crictl ps --name network-operator
    5. Exit from the debug shell.

5.5.4. Gathering Operator logs

If you experience Operator issues, you can gather detailed diagnostic information from Operator pod logs.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).
  • You have the fully qualified domain names of the control plane, or master machines.

Procedure

  1. List the Operator pods that are running in the Operator’s namespace, plus the pod status, restarts, and age:

    $ oc get pods -n <operator_namespace>
  2. Review logs for an Operator pod:

    $ oc logs pod/<pod_name> -n <operator_namespace>

    If an Operator pod has multiple containers, the preceding command will produce an error that includes the name of each container. Query logs from an individual container:

    $ oc logs pod/<operator_pod_name> -c <container_name> -n <operator_namespace>
  3. If the API is not functional, review Operator pod and container logs on each master node by using SSH instead. Replace <master-node>.<cluster_name>.<base_domain> with appropriate values.

    1. List pods on each master node:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl pods
    2. For any Operator pods not showing a Ready status, inspect the pod’s status in detail. Replace <operator_pod_id> with the Operator pod’s ID listed in the output of the preceding command:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl inspectp <operator_pod_id>
    3. List containers related to an Operator pod:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl ps --pod=<operator_pod_id>
    4. For any Operator container not showing a Ready status, inspect the container’s status in detail. Replace <container_id> with a container ID listed in the output of the preceding command:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl inspect <container_id>
    5. Review the logs for any Operator containers not showing a Ready status. Replace <container_id> with a container ID listed in the output of the preceding command:

      $ ssh core@<master-node>.<cluster_name>.<base_domain> sudo crictl logs -f <container_id>
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. Before attempting to collect diagnostic data over SSH, review whether the data collected by running oc adm must gather and other oc commands is sufficient instead. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain>.

5.5.5. Disabling the Machine Config Operator from automatically rebooting

When configuration changes are made by the Machine Config Operator, Red Hat Enterprise Linux CoreOS (RHCOS) must reboot for the changes to take effect. Whether the configuration change is automatic, such as when a kube-apiserver-to-kubelet-signer CA is rotated, or manual, such as when a registry or SSH key is updated, an RHCOS node reboots automatically unless it is paused.

To avoid unwanted disruptions, you can modify the machine config pool (MCP) to prevent automatic rebooting after the Operator makes changes to the machine config.

Note

Pausing a machine config pool stops all system reboot processes and all configuration changes from being applied.

5.5.5.1. Disabling the Machine Config Operator from automatically rebooting by using the console

To avoid unwanted disruptions from changes made by the Machine Config Operator (MCO), you can use the OpenShift Container Platform web console to modify the machine config pool (MCP) to prevent the MCO from making any changes to nodes in that pool. This prevents any reboots that would normally be part of the MCO update process.

Note

Pausing an MCP stops all updates to your RHCOS nodes, including updates to the operating system, security, certificate, and any other updates related to the machine config. Pausing should be done for short periods of time only.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.

Procedure

To pause or unpause automatic MCO update rebooting:

  • Pause the autoreboot process:

    1. Log in to the OpenShift Container Platform web console as a user with the cluster-admin role.
    2. Click ComputeMachine Config Pools.
    3. On the Machine Config Pools page, click either master or worker, depending upon which nodes you want to pause rebooting for.
    4. On the master or worker page, click YAML.
    5. In the YAML, update the spec.paused field to true.

      Sample MachineConfigPool object

      apiVersion: machineconfiguration.openshift.io/v1
      kind: MachineConfigPool
       ...
      spec:
       ...
        paused: true 1

      1
      Update the spec.paused field to true to pause rebooting.
    6. To verify that the MCP is paused, return to the Machine Config Pools page.

      On the Machine Config Pools page, the Paused column reports True for the MCP you modified.

      If the MCP has pending changes while paused, the Updated column is False and Updating is False. When Updated is True and Updating is False, there are no pending changes.

      Important

      If there are pending changes (where both the Updated and Updating columns are False), it is recommended to schedule a maintenance window for a reboot as early as possible. Use the following steps for unpausing the autoreboot process to apply the changes that were queued since the last reboot.

  • Unpause the autoreboot process:

    1. Log in to the OpenShift Container Platform web console as a user with the cluster-admin role.
    2. Click ComputeMachine Config Pools.
    3. On the Machine Config Pools page, click either master or worker, depending upon which nodes you want to pause rebooting for.
    4. On the master or worker page, click YAML.
    5. In the YAML, update the spec.paused field to false.

      Sample MachineConfigPool object

      apiVersion: machineconfiguration.openshift.io/v1
      kind: MachineConfigPool
       ...
      spec:
       ...
        paused: false 1

      1
      Update the spec.paused field to false to allow rebooting.
      Note

      By unpausing an MCP, the MCO applies all paused changes reboots Red Hat Enterprise Linux CoreOS (RHCOS) as needed.

    6. To verify that the MCP is paused, return to the Machine Config Pools page.

      On the Machine Config Pools page, the Paused column reports False for the MCP you modified.

      If the MCP is applying any pending changes, the Updated column is False and the Updating column is True. When Updated is True and Updating is False, there are no further changes being made.

5.5.5.2. Disabling the Machine Config Operator from automatically rebooting by using the CLI

To avoid unwanted disruptions from changes made by the Machine Config Operator (MCO), you can modify the machine config pool (MCP) using the OpenShift CLI (oc) to prevent the MCO from making any changes to nodes in that pool. This prevents any reboots that would normally be part of the MCO update process.

Note

Pausing an MCP stops all updates to your RHCOS nodes, including updates to the operating system, security, certificate, as well as any other updates related to the machine config. Pausing should be done for short periods of time only.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

To pause or unpause automatic MCO update rebooting:

  • Pause the autoreboot process:

    1. Update the MachineConfigPool custom resource to set the spec.paused field to true.

      Control plane (master) nodes

      $ oc patch --type=merge --patch='{"spec":{"paused":true}}' machineconfigpool/master

      Worker nodes

      $ oc patch --type=merge --patch='{"spec":{"paused":true}}' machineconfigpool/worker

    2. Verify that the MCP is paused:

      Control plane (master) nodes

      $ oc get machineconfigpool/master --template='{{.spec.paused}}'

      Worker nodes

      $ oc get machineconfigpool/worker --template='{{.spec.paused}}'

      Example output

      true

      The spec.paused field is true and the MCP is paused.

    3. Determine if the MCP has pending changes:

      # oc get machineconfigpool

      Example output

      NAME     CONFIG                                             UPDATED   UPDATING
      master   rendered-master-33cf0a1254318755d7b48002c597bf91   True      False
      worker   rendered-worker-e405a5bdb0db1295acea08bcca33fa60   False     False

      If the UPDATED column is False and UPDATING is False, there are pending changes. When UPDATED is True and UPDATING is False, there are no pending changes. In the previous example, the worker node has pending changes. The master node does not have any pending changes.

      Important

      If there are pending changes (where both the Updated and Updating columns are False), it is recommended to schedule a maintenance window for a reboot as early as possible. Use the following steps for unpausing the autoreboot process to apply the changes that were queued since the last reboot.

  • Unpause the autoreboot process:

    1. Update the MachineConfigPool custom resource to set the spec.paused field to false.

      Control plane (master) nodes

      $ oc patch --type=merge --patch='{"spec":{"paused":false}}' machineconfigpool/master

      Worker nodes

      $ oc patch --type=merge --patch='{"spec":{"paused":false}}' machineconfigpool/worker

      Note

      By unpausing an MCP, the MCO applies all paused changes and reboots Red Hat Enterprise Linux CoreOS (RHCOS) as needed.

    2. Verify that the MCP is unpaused:

      Control plane (master) nodes

      $ oc get machineconfigpool/master --template='{{.spec.paused}}'

      Worker nodes

      $ oc get machineconfigpool/worker --template='{{.spec.paused}}'

      Example output

      false

      The spec.paused field is false and the MCP is unpaused.

    3. Determine if the MCP has pending changes:

      $ oc get machineconfigpool

      Example output

      NAME     CONFIG                                   UPDATED  UPDATING
      master   rendered-master-546383f80705bd5aeaba93   True     False
      worker   rendered-worker-b4c51bb33ccaae6fc4a6a5   False    True

      If the MCP is applying any pending changes, the UPDATED column is False and the UPDATING column is True. When UPDATED is True and UPDATING is False, there are no further changes being made. In the previous example, the MCO is updating the worker node.

5.5.6. Refreshing failing subscriptions

In Operator Lifecycle Manager (OLM), if you subscribe to an Operator that references images that are not accessible on your network, you can find jobs in the openshift-marketplace namespace that are failing with the following errors:

Example output

ImagePullBackOff for
Back-off pulling image "example.com/openshift4/ose-elasticsearch-operator-bundle@sha256:6d2587129c846ec28d384540322b40b05833e7e00b25cca584e004af9a1d292e"

Example output

rpc error: code = Unknown desc = error pinging docker registry example.com: Get "https://example.com/v2/": dial tcp: lookup example.com on 10.0.0.1:53: no such host

As a result, the subscription is stuck in this failing state and the Operator is unable to install or upgrade.

You can refresh a failing subscription by deleting the subscription, cluster service version (CSV), and other related objects. After recreating the subscription, OLM then reinstalls the correct version of the Operator.

Prerequisites

  • You have a failing subscription that is unable to pull an inaccessible bundle image.
  • You have confirmed that the correct bundle image is accessible.

Procedure

  1. Get the names of the Subscription and ClusterServiceVersion objects from the namespace where the Operator is installed:

    $ oc get sub,csv -n <namespace>

    Example output

    NAME                                                       PACKAGE                  SOURCE             CHANNEL
    subscription.operators.coreos.com/elasticsearch-operator   elasticsearch-operator   redhat-operators   5.0
    
    NAME                                                                         DISPLAY                            VERSION    REPLACES   PHASE
    clusterserviceversion.operators.coreos.com/elasticsearch-operator.5.0.0-65   OpenShift Elasticsearch Operator   5.0.0-65              Succeeded

  2. Delete the subscription:

    $ oc delete subscription <subscription_name> -n <namespace>
  3. Delete the cluster service version:

    $ oc delete csv <csv_name> -n <namespace>
  4. Get the names of any failing jobs and related config maps in the openshift-marketplace namespace:

    $ oc get job,configmap -n openshift-marketplace

    Example output

    NAME                                                                        COMPLETIONS   DURATION   AGE
    job.batch/1de9443b6324e629ddf31fed0a853a121275806170e34c926d69e53a7fcbccb   1/1           26s        9m30s
    
    NAME                                                                        DATA   AGE
    configmap/1de9443b6324e629ddf31fed0a853a121275806170e34c926d69e53a7fcbccb   3      9m30s

  5. Delete the job:

    $ oc delete job <job_name> -n openshift-marketplace

    This ensures pods that try to pull the inaccessible image are not recreated.

  6. Delete the config map:

    $ oc delete configmap <configmap_name> -n openshift-marketplace
  7. Reinstall the Operator using OperatorHub in the web console.

Verification

  • Check that the Operator has been reinstalled successfully:

    $ oc get sub,csv,installplan -n <namespace>

5.6. Investigating pod issues

OpenShift Container Platform leverages the Kubernetes concept of a pod, which is one or more containers deployed together on one host. A pod is the smallest compute unit that can be defined, deployed, and managed on OpenShift Container Platform 4.6.

After a pod is defined, it is assigned to run on a node until its containers exit, or until it is removed. Depending on policy and exit code, Pods are either removed after exiting or retained so that their logs can be accessed.

The first thing to check when pod issues arise is the pod’s status. If an explicit pod failure has occurred, observe the pod’s error state to identify specific image, container, or pod network issues. Focus diagnostic data collection according to the error state. Review pod event messages, as well as pod and container log information. Diagnose issues dynamically by accessing running Pods on the command line, or start a debug pod with root access based on a problematic pod’s deployment configuration.

5.6.1. Understanding pod error states

Pod failures return explicit error states that can be observed in the status field in the output of oc get pods. Pod error states cover image, container, and container network related failures.

The following table provides a list of pod error states along with their descriptions.

Table 5.2. Pod error states

Pod error stateDescription

ErrImagePull

Generic image retrieval error.

ErrImagePullBackOff

Image retrieval failed and is backed off.

ErrInvalidImageName

The specified image name was invalid.

ErrImageInspect

Image inspection did not succeed.

ErrImageNeverPull

PullPolicy is set to NeverPullImage and the target image is not present locally on the host.

ErrRegistryUnavailable

When attempting to retrieve an image from a registry, an HTTP error was encountered.

ErrContainerNotFound

The specified container is either not present or not managed by the kubelet, within the declared pod.

ErrRunInitContainer

Container initialization failed.

ErrRunContainer

None of the pod’s containers started successfully.

ErrKillContainer

None of the pod’s containers were killed successfully.

ErrCrashLoopBackOff

A container has terminated. The kubelet will not attempt to restart it.

ErrVerifyNonRoot

A container or image attempted to run with root privileges.

ErrCreatePodSandbox

Pod sandbox creation did not succeed.

ErrConfigPodSandbox

Pod sandbox configuration was not obtained.

ErrKillPodSandbox

A pod sandbox did not stop successfully.

ErrSetupNetwork

Network initialization failed.

ErrTeardownNetwork

Network termination failed.

5.6.2. Reviewing pod status

You can query pod status and error states. You can also query a pod’s associated deployment configuration and review base image availability.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • skopeo is installed.

Procedure

  1. Switch into a project:

    $ oc project <project_name>
  2. List pods running within the namespace, as well as pod status, error states, restarts, and age:

    $ oc get pods
  3. Determine whether the namespace is managed by a deployment configuration:

    $ oc status

    If the namespace is managed by a deployment configuration, the output includes the deployment configuration name and a base image reference.

  4. Inspect the base image referenced in the preceding command’s output:

    $ skopeo inspect docker://<image_reference>
  5. If the base image reference is not correct, update the reference in the deployment configuration:

    $ oc edit deployment/my-deployment
  6. When deployment configuration changes on exit, the configuration will automatically redeploy. Watch pod status as the deployment progresses, to determine whether the issue has been resolved:

    $ oc get pods -w
  7. Review events within the namespace for diagnostic information relating to pod failures:

    $ oc get events

5.6.3. Inspecting pod and container logs

You can inspect pod and container logs for warnings and error messages related to explicit pod failures. Depending on policy and exit code, pod and container logs remain available after pods have been terminated.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Query logs for a specific pod:

    $ oc logs <pod_name>
  2. Query logs for a specific container within a pod:

    $ oc logs <pod_name> -c <container_name>

    Logs retrieved using the preceding oc logs commands are composed of messages sent to stdout within pods or containers.

  3. Inspect logs contained in /var/log/ within a pod.

    1. List log files and subdirectories contained in /var/log within a pod:

      $ oc exec <pod_name> ls -alh /var/log
    2. Query a specific log file contained in /var/log within a pod:

      $ oc exec <pod_name> cat /var/log/<path_to_log>
    3. List log files and subdirectories contained in /var/log within a specific container:

      $ oc exec <pod_name> -c <container_name> ls /var/log
    4. Query a specific log file contained in /var/log within a specific container:

      $ oc exec <pod_name> -c <container_name> cat /var/log/<path_to_log>

5.6.4. Accessing running pods

You can review running pods dynamically by opening a shell inside a pod or by gaining network access through port forwarding.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Switch into the project that contains the pod you would like to access. This is necessary because the oc rsh command does not accept the -n namespace option:

    $ oc project <namespace>
  2. Start a remote shell into a pod:

    $ oc rsh <pod_name>  1
    1
    If a pod has multiple containers, oc rsh defaults to the first container unless -c <container_name> is specified.
  3. Start a remote shell into a specific container within a pod:

    $ oc rsh -c <container_name> pod/<pod_name>
  4. Create a port forwarding session to a port on a pod:

    $ oc port-forward <pod_name> <host_port>:<pod_port>  1
    1
    Enter Ctrl+C to cancel the port forwarding session.

5.6.5. Starting debug pods with root access

You can start a debug pod with root access, based on a problematic pod’s deployment or deployment configuration. Pod users typically run with non-root privileges, but running troubleshooting pods with temporary root privileges can be useful during issue investigation.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Start a debug pod with root access, based on a deployment.

    1. Obtain a project’s deployment name:

      $ oc get deployment -n <project_name>
    2. Start a debug pod with root privileges, based on the deployment:

      $ oc debug deployment/my-deployment --as-root -n <project_name>
  2. Start a debug pod with root access, based on a deployment configuration.

    1. Obtain a project’s deployment configuration name:

      $ oc get deploymentconfigs -n <project_name>
    2. Start a debug pod with root privileges, based on the deployment configuration:

      $ oc debug deploymentconfig/my-deployment-configuration --as-root -n <project_name>
Note

You can append -- <command> to the preceding oc debug commands to run individual commands within a debug pod, instead of running an interactive shell.

5.6.6. Copying files to and from pods and containers

You can copy files to and from a pod to test configuration changes or gather diagnostic information.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Copy a file to a pod:

    $ oc cp <local_path> <pod_name>:/<path> -c <container_name>  1
    1
    The first container in a pod is selected if the -c option is not specified.
  2. Copy a file from a pod:

    $ oc cp <pod_name>:/<path>  -c <container_name><local_path>  1
    1
    The first container in a pod is selected if the -c option is not specified.
    Note

    For oc cp to function, the tar binary must be available within the container.

5.7. Troubleshooting the Source-to-Image process

5.7.1. Strategies for Source-to-Image troubleshooting

Use Source-to-Image (S2I) to build reproducible, Docker-formatted container images. You can create ready-to-run images by injecting application source code into a container image and assembling a new image. The new image incorporates the base image (the builder) and built source.

To determine where in the S2I process a failure occurs, you can observe the state of the pods relating to each of the following S2I stages:

  1. During the build configuration stage, a build pod is used to create an application container image from a base image and application source code.
  2. During the deployment configuration stage, a deployment pod is used to deploy application pods from the application container image that was built in the build configuration stage. The deployment pod also deploys other resources such as services and routes. The deployment configuration begins after the build configuration succeeds.
  3. After the deployment pod has started the application pods, application failures can occur within the running application pods. For instance, an application might not behave as expected even though the application pods are in a Running state. In this scenario, you can access running application pods to investigate application failures within a pod.

When troubleshooting S2I issues, follow this strategy:

  1. Monitor build, deployment, and application pod status
  2. Determine the stage of the S2I process where the problem occurred
  3. Review logs corresponding to the failed stage

5.7.2. Gathering Source-to-Image diagnostic data

The S2I tool runs a build pod and a deployment pod in sequence. The deployment pod is responsible for deploying the application pods based on the application container image created in the build stage. Watch build, deployment and application pod status to determine where in the S2I process a failure occurs. Then, focus diagnostic data collection accordingly.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • Your API service is still functional.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. Watch the pod status throughout the S2I process to determine at which stage a failure occurs:

    $ oc get pods -w  1
    1
    Use -w to monitor pods for changes until you quit the command using Ctrl+C.
  2. Review a failed pod’s logs for errors.

    • If the build pod fails, review the build pod’s logs:

      $ oc logs -f pod/<application_name>-<build_number>-build
      Note

      Alternatively, you can review the build configuration’s logs using oc logs -f bc/<application_name>. The build configuration’s logs include the logs from the build pod.

    • If the deployment pod fails, review the deployment pod’s logs:

      $ oc logs -f pod/<application_name>-<build_number>-deploy
      Note

      Alternatively, you can review the deployment configuration’s logs using oc logs -f dc/<application_name>. This outputs logs from the deployment pod until the deployment pod completes successfully. The command outputs logs from the application pods if you run it after the deployment pod has completed. After a deployment pod completes, its logs can still be accessed by running oc logs -f pod/<application_name>-<build_number>-deploy.

    • If an application pod fails, or if an application is not behaving as expected within a running application pod, review the application pod’s logs:

      $ oc logs -f pod/<application_name>-<build_number>-<random_string>

5.7.3. Gathering application diagnostic data to investigate application failures

Application failures can occur within running application pods. In these situations, you can retrieve diagnostic information with these strategies:

  • Review events relating to the application pods.
  • Review the logs from the application pods, including application-specific log files that are not collected by the OpenShift Container Platform logging framework.
  • Test application functionality interactively and run diagnostic tools in an application container.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. List events relating to a specific application pod. The following example retrieves events for an application pod named my-app-1-akdlg:

    $ oc describe pod/my-app-1-akdlg
  2. Review logs from an application pod:

    $ oc logs -f pod/my-app-1-akdlg
  3. Query specific logs within a running application pod. Logs that are sent to stdout are collected by the OpenShift Container Platform logging framework and are included in the output of the preceding command. The following query is only required for logs that are not sent to stdout.

    1. If an application log can be accessed without root privileges within a pod, concatenate the log file as follows:

      $ oc exec my-app-1-akdlg -- cat /var/log/my-application.log
    2. If root access is required to view an application log, you can start a debug container with root privileges and then view the log file from within the container. Start the debug container from the project’s DeploymentConfig object. Pod users typically run with non-root privileges, but running troubleshooting pods with temporary root privileges can be useful during issue investigation:

      $ oc debug dc/my-deployment-configuration --as-root -- cat /var/log/my-application.log
      Note

      You can access an interactive shell with root access within the debug pod if you run oc debug dc/<deployment_configuration> --as-root without appending -- <command>.

  4. Test application functionality interactively and run diagnostic tools, in an application container with an interactive shell.

    1. Start an interactive shell on the application container:

      $ oc exec -it my-app-1-akdlg /bin/bash
    2. Test application functionality interactively from within the shell. For example, you can run the container’s entry point command and observe the results. Then, test changes from the command line directly, before updating the source code and rebuilding the application container through the S2I process.
    3. Run diagnostic binaries available within the container.

      Note

      Root privileges are required to run some diagnostic binaries. In these situations you can start a debug pod with root access, based on a problematic pod’s DeploymentConfig object, by running oc debug dc/<deployment_configuration> --as-root. Then, you can run diagnostic binaries as root from within the debug pod.

  5. If diagnostic binaries are not available within a container, you can run a host’s diagnostic binaries within a container’s namespace by using nsenter. The following example runs ip ad within a container’s namespace, using the host`s ip binary.

    1. Enter into a debug session on the target node. This step instantiates a debug pod called <node_name>-debug:

      $ oc debug node/my-cluster-node
    2. Set /host as the root directory within the debug shell. The debug pod mounts the host’s root file system in /host within the pod. By changing the root directory to /host, you can run binaries contained in the host’s executable paths:

      # chroot /host
      Note

      OpenShift Container Platform 4.6 cluster nodes running Red Hat Enterprise Linux CoreOS (RHCOS) are immutable and rely on Operators to apply cluster changes. Accessing cluster nodes using SSH is not recommended and nodes will be tainted as accessed. However, if the OpenShift Container Platform API is not available, or the kubelet is not properly functioning on the target node, oc operations will be impacted. In such situations, it is possible to access nodes using ssh core@<node>.<cluster_name>.<base_domain> instead.

    3. Determine the target container ID:

      # crictl ps
    4. Determine the container’s process ID. In this example, the target container ID is a7fe32346b120:

      # crictl inspect a7fe32346b120 --output yaml | grep 'pid:' | awk '{print $2}'
    5. Run ip ad within the container’s namespace, using the host’s ip binary. This example uses 31150 as the container’s process ID. The nsenter command enters the namespace of a target process and runs a command in its namespace. Because the target process in this example is a container’s process ID, the ip ad command is run in the container’s namespace from the host:

      # nsenter -n -t 31150 -- ip ad
      Note

      Running a host’s diagnostic binaries within a container’s namespace is only possible if you are using a privileged container such as a debug node.

5.7.4. Additional resources

5.8. Troubleshooting storage issues

5.8.1. Resolving multi-attach errors

When a node crashes or shuts down abruptly, the attached ReadWriteOnce (RWO) volume is expected to be unmounted from the node so that it can be used by a pod scheduled on another node.

However, mounting on a new node is not possible because the failed node is unable to unmount the attached volume.

A multi-attach error is reported:

Example output

Unable to attach or mount volumes: unmounted volumes=[sso-mysql-pvol], unattached volumes=[sso-mysql-pvol default-token-x4rzc]: timed out waiting for the condition
Multi-Attach error for volume "pvc-8837384d-69d7-40b2-b2e6-5df86943eef9" Volume is already used by pod(s) sso-mysql-1-ns6b4

Procedure

To resolve the multi-attach issue, use one of the following solutions:

  • Enable multiple attachments by using RWX volumes.

    For most storage solutions, you can use ReadWriteMany (RWX) volumes to prevent multi-attach errors.

  • Recover or delete the failed node when using an RWO volume.

    For storage that does not support RWX, such as VMware vSphere, RWO volumes must be used instead. However, RWO volumes cannot be mounted on multiple nodes.

    If you encounter a multi-attach error message with an RWO volume, force delete the pod on a shutdown or crashed node to avoid data loss in critical workloads, such as when dynamic persistent volumes are attached.

    $ oc delete pod <old_pod> --force=true --grace-period=0s

    This command deletes the volumes stuck on shutdown or crashed nodes after six minutes.

5.9. Troubleshooting Windows container workload issues

5.9.1. Windows Machine Config Operator does not install

If you have completed the process of installing the Windows Machine Config Operator (WMCO), but the Operator is stuck in the InstallWaiting phase, your issue is likely caused by a networking issue.

The WMCO requires your OpenShift Container Platform cluster to be configured with hybrid networking using OVN-Kubernetes; the WMCO cannot complete the installation process without hybrid networking available. This is necessary to manage nodes on multiple operating systems (OS) and OS variants. This must be completed during the installation of your cluster.

For more information, see Configuring hybrid networking.

5.9.2. Investigating why Windows Machine does not become compute node

There are various reasons why a Windows Machine does not become a compute node. The best way to investigate this problem is to collect the Windows Machine Config Operator (WMCO) logs.

Prerequisites

  • You installed the Windows Machine Config Operator (WMCO) using Operator Lifecycle Manager (OLM).
  • You have created a Windows machine set.

Procedure

  • Run the following command to collect the WMCO logs:

    $ oc logs -f $(oc get pods -o jsonpath={.items[0].metadata.name} -n openshift-windows-machine-config-operator) -n openshift-windows-machine-config-operator

5.9.3. Accessing a Windows node

Windows nodes cannot be accessed using the oc debug node command; the command requires running a privileged pod on the node, which is not yet supported for Windows. Instead, a Windows node can be accessed using a secure shell (SSH) or Remote Desktop Protocol (RDP). An SSH bastion is required for both methods.

5.9.3.1. Accessing a Windows node using SSH

You can access a Windows node by using a secure shell (SSH).

Prerequisites

  • You have installed the Windows Machine Config Operator (WMCO) using Operator Lifecycle Manager (OLM).
  • You have created a Windows machine set.
  • You have added the key used in the cloud-private-key secret and the key used when creating the cluster to the ssh-agent. For security reasons, remember to remove the keys from the ssh-agent after use.
  • You have connected to the Windows node using an ssh-bastion pod.

Procedure

  • Access the Windows node by running the following command:

    $ ssh -t -o StrictHostKeyChecking=no -o ProxyCommand='ssh -A -o StrictHostKeyChecking=no \
        -o ServerAliveInterval=30 -W %h:%p core@$(oc get service --all-namespaces -l run=ssh-bastion \
        -o go-template="{{ with (index (index .items 0).status.loadBalancer.ingress 0) }}{{ or .hostname .ip }}{{end}}")' <username>@<windows_node_internal_ip> 1 2
    1
    Specify the cloud provider username, such as Administrator for Amazon Web Services (AWS) or capi for Microsoft Azure.
    2
    Specify the internal IP address of the node, which can be discovered by running the following command:
    $ oc get nodes <node_name> -o jsonpath={.status.addresses[?\(@.type==\"InternalIP\"\)].address}

5.9.3.2. Accessing a Windows node using RDP

You can access a Windows node by using a Remote Desktop Protocol (RDP).

Prerequisites

  • You installed the Windows Machine Config Operator (WMCO) using Operator Lifecycle Manager (OLM).
  • You have created a Windows machine set.
  • You have added the key used in the cloud-private-key secret and the key used when creating the cluster to the ssh-agent. For security reasons, remember to remove the keys from the ssh-agent after use.
  • You have connected to the Windows node using an ssh-bastion pod.

Procedure

  1. Run the following command to set up an SSH tunnel:

    $ ssh -L 2020:<windows_node_internal_ip>:3389 \ 1
        core@$(oc get service --all-namespaces -l run=ssh-bastion -o go-template="{{ with (index (index .items 0).status.loadBalancer.ingress 0) }}{{ or .hostname .ip }}{{end}}")
    1
    Specify the internal IP address of the node, which can be discovered by running the following command:
    $ oc get nodes <node_name> -o jsonpath={.status.addresses[?\(@.type==\"InternalIP\"\)].address}
  2. From within the resulting shell, SSH into the Windows node and run the following command to create a password for the user:

    C:\> net user <username> * 1
    1
    Specify the cloud provider user name, such as Administrator for AWS or capi for Azure.

You can now remotely access the Windows node at localhost:2020 using an RDP client.

5.9.4. Collecting Kubernetes node logs for Windows containers

Windows container logging works differently from Linux container logging; the Kubernetes node logs for Windows workloads are streamed to the C:\var\logs directory by default. Therefore, you must gather the Windows node logs from that directory.

Prerequisites

  • You installed the Windows Machine Config Operator (WMCO) using Operator Lifecycle Manager (OLM).
  • You have created a Windows machine set.

Procedure

  1. To view the logs under all directories in C:\var\logs, run the following command:

    $ oc adm node-logs -l kubernetes.io/os=windows --path= \
        /ip-10-0-138-252.us-east-2.compute.internal containers \
        /ip-10-0-138-252.us-east-2.compute.internal hybrid-overlay \
        /ip-10-0-138-252.us-east-2.compute.internal kube-proxy \
        /ip-10-0-138-252.us-east-2.compute.internal kubelet \
        /ip-10-0-138-252.us-east-2.compute.internal pods
  2. You can now list files in the directories using the same command and view the individual log files. For example, to view the kubelet logs, run the following command:

    $ oc adm node-logs -l kubernetes.io/os=windows --path=/kubelet/kubelet.log

5.9.5. Collecting Windows application event logs

The Get-WinEvent shim on the kubelet logs endpoint can be used to collect application event logs from Windows machines.

Prerequisites

  • You installed the Windows Machine Config Operator (WMCO) using Operator Lifecycle Manager (OLM).
  • You have created a Windows machine set.

Procedure

  • To view logs from all applications logging to the event logs on the Windows machine, run:

    $ oc adm node-logs -l kubernetes.io/os=windows --path=journal

    The same command is executed when collecting logs with oc adm must-gather.

    Other Windows application logs from the event log can also be collected by specifying the respective service with a -u flag. For example, you can run the following command to collect logs for the docker runtime service:

    $ oc adm node-logs -l kubernetes.io/os=windows --path=journal -u docker

5.9.6. Collecting Docker logs for Windows containers

The Windows Docker service does not stream its logs to stdout, but instead, logs to the event log for Windows. You can view the Docker event logs to investigate issues you think might be caused by the Windows Docker service.

Prerequisites

  • You installed the Windows Machine Config Operator (WMCO) using Operator Lifecycle Manager (OLM).
  • You have created a Windows machine set.

Procedure

  1. SSH into the Windows node and enter PowerShell:

    C:\> powershell
  2. View the Docker logs by running the following command:

    C:\> Get-EventLog -LogName Application -Source Docker

5.9.7. Additional resources

5.10. Investigating monitoring issues

OpenShift Container Platform includes a pre-configured, pre-installed, and self-updating monitoring stack that provides monitoring for core platform components. In OpenShift Container Platform 4.6, cluster administrators can optionally enable monitoring for user-defined projects.

You can follow these procedures if your own metrics are unavailable or if Prometheus is consuming a lot of disk space.

5.10.1. Investigating why user-defined metrics are unavailable

ServiceMonitor resources enable you to determine how to use the metrics exposed by a service in user-defined projects. Follow the steps outlined in this procedure if you have created a ServiceMonitor resource but cannot see any corresponding metrics in the Metrics UI.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).
  • You have enabled and configured monitoring for user-defined workloads.
  • You have created the user-workload-monitoring-config ConfigMap object.
  • You have created a ServiceMonitor resource.

Procedure

  1. Check that the corresponding labels match in the service and ServiceMonitor resource configurations.

    1. Obtain the label defined in the service. The following example queries the prometheus-example-app service in the ns1 project:

      $ oc -n ns1 get service prometheus-example-app -o yaml

      Example output

        labels:
          app: prometheus-example-app

    2. Check that the matchLabels app label in the ServiceMonitor resource configuration matches the label output in the preceding step:

      $ oc -n ns1 get servicemonitor prometheus-example-monitor -o yaml

      Example output

      spec:
        endpoints:
        - interval: 30s
          port: web
          scheme: http
        selector:
          matchLabels:
            app: prometheus-example-app

      Note

      You can check service and ServiceMonitor resource labels as a developer with view permissions for the project.

  2. Inspect the logs for the Prometheus Operator in the openshift-user-workload-monitoring project.

    1. List the pods in the openshift-user-workload-monitoring project:

      $ oc -n openshift-user-workload-monitoring get pods

      Example output

      NAME                                   READY   STATUS    RESTARTS   AGE
      prometheus-operator-776fcbbd56-2nbfm   2/2     Running   0          132m
      prometheus-user-workload-0             5/5     Running   1          132m
      prometheus-user-workload-1             5/5     Running   1          132m
      thanos-ruler-user-workload-0           3/3     Running   0          132m
      thanos-ruler-user-workload-1           3/3     Running   0          132m

    2. Obtain the logs from the prometheus-operator container in the prometheus-operator pod. In the following example, the pod is called prometheus-operator-776fcbbd56-2nbfm:

      $ oc -n openshift-user-workload-monitoring logs prometheus-operator-776fcbbd56-2nbfm -c prometheus-operator

      If there is a issue with the service monitor, the logs might include an error similar to this example:

      level=warn ts=2020-08-10T11:48:20.906739623Z caller=operator.go:1829 component=prometheusoperator msg="skipping servicemonitor" error="it accesses file system via bearer token file which Prometheus specification prohibits" servicemonitor=eagle/eagle namespace=openshift-user-workload-monitoring prometheus=user-workload
  3. Review the target status for your project in the Prometheus UI directly.

    1. Establish port-forwarding to the Prometheus instance in the openshift-user-workload-monitoring project:

      $ oc port-forward -n openshift-user-workload-monitoring pod/prometheus-user-workload-0 9090
    2. Open http://localhost:9090/targets in a web browser and review the status of the target for your project directly in the Prometheus UI. Check for error messages relating to the target.
  4. Configure debug level logging for the Prometheus Operator in the openshift-user-workload-monitoring project.

    1. Edit the user-workload-monitoring-config ConfigMap object in the openshift-user-workload-monitoring project:

      $ oc -n openshift-user-workload-monitoring edit configmap user-workload-monitoring-config
    2. Add logLevel: debug for prometheusOperator under data/config.yaml to set the log level to debug:

      apiVersion: v1
      kind: ConfigMap
      metadata:
        name: user-workload-monitoring-config
        namespace: openshift-user-workload-monitoring
      data:
        config.yaml: |
          prometheusOperator:
            logLevel: debug
    3. Save the file to apply the changes.

      Note

      The prometheus-operator in the openshift-user-workload-monitoring project restarts automatically when you apply the log-level change.

    4. Confirm that the debug log-level has been applied to the prometheus-operator deployment in the openshift-user-workload-monitoring project:

      $ oc -n openshift-user-workload-monitoring get deploy prometheus-operator -o yaml |  grep "log-level"

      Example output

              - --log-level=debug

      Debug level logging will show all calls made by the Prometheus Operator.

    5. Check that the prometheus-operator pod is running:

      $ oc -n openshift-user-workload-monitoring get pods
      Note

      If an unrecognized Prometheus Operator loglevel value is included in the config map, the prometheus-operator pod might not restart successfully.

    6. Review the debug logs to see if the Prometheus Operator is using the ServiceMonitor resource. Review the logs for other related errors.

Additional resources

5.10.2. Determining why Prometheus is consuming a lot of disk space

Developers can create labels to define attributes for metrics in the form of key-value pairs. The number of potential key-value pairs corresponds to the number of possible values for an attribute. An attribute that has an unlimited number of potential values is called an unbound attribute. For example, a customer_id attribute is unbound because it has an infinite number of possible values.

Every assigned key-value pair has a unique time series. The use of many unbound attributes in labels can result in an exponential increase in the number of time series created. This can impact Prometheus performance and can consume a lot of disk space.

You can use the following measures when Prometheus consumes a lot of disk:

  • Check the number of scrape samples that are being collected.
  • Check the time series database (TSDB) status in the Prometheus UI for more information on which labels are creating the most time series. This requires cluster administrator privileges.
  • Reduce the number of unique time series that are created by reducing the number of unbound attributes that are assigned to user-defined metrics.

    Note

    Using attributes that are bound to a limited set of possible values reduces the number of potential key-value pair combinations.

  • Enforce limits on the number of samples that can be scraped across user-defined projects. This requires cluster administrator privileges.

Prerequisites

  • You have access to the cluster as a user with the cluster-admin role.
  • You have installed the OpenShift CLI (oc).

Procedure

  1. In the Administrator perspective, navigate to MonitoringMetrics.
  2. Run the following Prometheus Query Language (PromQL) query in the Expression field. This returns the ten metrics that have the highest number of scrape samples:

    topk(10,count by (job)({__name__=~".+"}))
  3. Investigate the number of unbound label values assigned to metrics with higher than expected scrape sample counts.

    • If the metrics relate to a user-defined project, review the metrics key-value pairs assigned to your workload. These are implemented through Prometheus client libraries at the application level. Try to limit the number of unbound attributes referenced in your labels.
    • If the metrics relate to a core OpenShift Container Platform project, create a Red Hat support case on the Red Hat Customer Portal.
  4. Check the TSDB status in the Prometheus UI.

    1. In the Administrator perspective, navigate to NetworkingRoutes.
    2. Select the openshift-monitoring project in the Project list.
    3. Select the URL in the prometheus-k8s row to open the login page for the Prometheus UI.
    4. Choose Log in with OpenShift to log in using your OpenShift Container Platform credentials.
    5. In the Prometheus UI, navigate to StatusTSDB Status.

Additional resources

5.11. Diagnosing OpenShift CLI (oc) issues

5.11.1. Understanding OpenShift CLI (oc) log levels

With the OpenShift CLI (oc), you can create applications and manage OpenShift Container Platform projects from a terminal.

If oc command-specific issues arise, increase the oc log level to output API request, API response, and curl request details generated by the command. This provides a granular view of a particular oc command’s underlying operation, which in turn might provide insight into the nature of a failure.

oc log levels range from 1 to 10. The following table provides a list of oc log levels, along with their descriptions.

Table 5.3. OpenShift CLI (oc) log levels

Log levelDescription

1 to 5

No additional logging to stderr.

6

Log API requests to stderr.

7

Log API requests and headers to stderr.

8

Log API requests, headers, and body, plus API response headers and body to stderr.

9

Log API requests, headers, and body, API response headers and body, plus curl requests to stderr.

10

Log API requests, headers, and body, API response headers and body, plus curl requests to stderr, in verbose detail.

5.11.2. Specifying OpenShift CLI (oc) log levels

You can investigate OpenShift CLI (oc) issues by increasing the command’s log level.

Prerequisites

  • You have installed the OpenShift CLI (oc).

Procedure

  1. Specify the oc log level when running an oc command:

    $ oc <options> --loglevel <log_level>
  2. The OpenShift Container Platform user’s current session token is typically included in logged curl requests where required. You can also obtain the current user’s session token manually, for use when testing aspects of an oc command’s underlying process step by step:

    $ oc whoami -t

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