2.3. Installing cluster logging using the CLI

You can use the OpenShift Container Platform CLI to install the Elasticsearch and Cluster Logging operators.

Prerequisites

  • Ensure that you have the necessary persistent storage for Elasticsearch. Note that each Elasticsearch node requires its own storage volume.

    注意

    If you use a local volume for persistent storage, do not use a raw block volume, which is described with volumeMode: block in the LocalVolume object. Elasticsearch cannot use raw block volumes.

    Elasticsearch is a memory-intensive application. By default, OpenShift Container Platform installs three Elasticsearch nodes with memory requests and limits of 16 GB. This initial set of three OpenShift Container Platform nodes might not have enough memory to run Elasticsearch within your cluster. If you experience memory issues that are related to Elasticsearch, add more Elasticsearch nodes to your cluster rather than increasing the memory on existing nodes.

Procedure

To install the Elasticsearch Operator and Cluster Logging Operator using the CLI:

  1. Create a Namespace for the Elasticsearch Operator.

    1. Create a Namespace object YAML file (for example, eo-namespace.yaml) for the Elasticsearch Operator: 

      apiVersion: v1
kind: Namespace
metadata:
  name: openshift-operators-redhat 1
  annotations:
    openshift.io/node-selector: ""
  labels:
    openshift.io/cluster-monitoring: "true" 2
      1
      You must specify the openshift-operators-redhat Namespace. To prevent possible conflicts with metrics, you should configure the Prometheus Cluster Monitoring stack to scrape metrics from the openshift-operators-redhat Namespace and not the openshift-operators Namespace. The openshift-operators Namespace might contain Community Operators, which are untrusted and could publish a metric with the same name as an OpenShift Container Platform metric, which would cause conflicts.
      2
      You must specify this label as shown to ensure that cluster monitoring scrapes the openshift-operators-redhat Namespace.

    2. Create the Namespace: 

      $ oc create -f <file-name>.yaml

      For example: 

      $ oc create -f eo-namespace.yaml

  2. Create a Namespace for the Cluster Logging Operator:

    1. Create a Namespace object YAML file (for example, clo-namespace.yaml) for the Cluster Logging Operator: 

      apiVersion: v1
kind: Namespace
metadata:
  name: openshift-logging
  annotations:
    openshift.io/node-selector: ""
  labels:
    openshift.io/cluster-monitoring: "true"

    2. Create the Namespace: 

      $ oc create -f <file-name>.yaml

      For example: 

      $ oc create -f clo-namespace.yaml

  3. Install the Elasticsearch Operator by creating the following objects:

    1. Create an Operator Group object YAML file (for example, eo-og.yaml) for the Elasticsearch operator: 

      apiVersion: operators.coreos.com/v1
kind: OperatorGroup
metadata:
  name: openshift-operators-redhat
  namespace: openshift-operators-redhat 1
spec: {}
      1
      You must specify the openshift-operators-redhat Namespace.

    2. Create an Operator Group object: 

      $ oc create -f <file-name>.yaml

      For example: 

      $ oc create -f eo-og.yaml

    3. Create a Subscription object YAML file (for example, eo-sub.yaml) to subscribe a Namespace to the Elasticsearch Operator.

      Example Subscription

      apiVersion: operators.coreos.com/v1alpha1
kind: Subscription
metadata:
  name: "elasticsearch-operator"
  namespace: "openshift-operators-redhat" 1
spec:
  channel: "4.5" 2
  installPlanApproval: "Automatic"
  source: "redhat-operators" 3
  sourceNamespace: "openshift-marketplace"
  name: "elasticsearch-operator"

      1
      You must specify the openshift-operators-redhat Namespace.
      2
      Specify 4.5 as the channel.
      3
      Specify redhat-operators. If your OpenShift Container Platform cluster is installed on a restricted network, also known as a disconnected cluster, specify the name of the CatalogSource object created when you configured the Operator Lifecycle Manager (OLM).

    4. Create the Subscription object: 

      $ oc create -f <file-name>.yaml

      For example: 

      $ oc create -f eo-sub.yaml

      The Elasticsearch Operator is installed to the openshift-operators-redhat Namespace and copied to each project in the cluster.

    5. Verify the Operator installation: 

      $ oc get csv --all-namespaces

      Example output

      NAMESPACE                                               NAME                                            DISPLAY                  VERSION               REPLACES   PHASE
default                                                 elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
kube-node-lease                                         elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
kube-public                                             elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
kube-system                                             elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
openshift-apiserver-operator                            elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
openshift-apiserver                                     elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
openshift-authentication-operator                       elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
openshift-authentication                                elasticsearch-operator.4.5.0-202007012112.p0    Elasticsearch Operator   4.5.0-202007012112.p0               Succeeded
...

      There should be an Elasticsearch Operator in each Namespace. The version number might be different than shown.

  4. Install the Cluster Logging Operator by creating the following objects:

    1. Create an OperatorGroup object YAML file (for example, clo-og.yaml) for the Cluster Logging Operator: 

      apiVersion: operators.coreos.com/v1
kind: OperatorGroup
metadata:
  name: cluster-logging
  namespace: openshift-logging 1
spec:
  targetNamespaces:
  - openshift-logging 2
      1 2
      You must specify the openshift-logging namespace.

    2. Create the OperatorGroup object: 

      $ oc create -f <file-name>.yaml

      For example: 

      $ oc create -f clo-og.yaml

    3. Create a Subscription object YAML file (for example, clo-sub.yaml) to subscribe a Namespace to the Cluster Logging Operator. 

      apiVersion: operators.coreos.com/v1alpha1
kind: Subscription
metadata:
  name: cluster-logging
  namespace: openshift-logging 1
spec:
  channel: "4.5" 2
  name: cluster-logging
  source: redhat-operators 3
  sourceNamespace: openshift-marketplace
      1
      You must specify the openshift-logging Namespace.
      2
      Specify 4.5 as the channel.
      3
      Specify redhat-operators. If your OpenShift Container Platform cluster is installed on a restricted network, also known as a disconnected cluster, specify the name of the CatalogSource object you created when you configured the Operator Lifecycle Manager (OLM).

    4. Create the Subscription object: 

      $ oc create -f <file-name>.yaml

      For example: 

      $ oc create -f clo-sub.yaml

      The Cluster Logging Operator is installed to the openshift-logging Namespace.

    5. Verify the Operator installation.

      There should be a Cluster Logging Operator in the openshift-logging Namespace. The Version number might be different than shown. 

      $ oc get csv -n openshift-logging

      Example output

      NAMESPACE                                               NAME                                         DISPLAY                  VERSION               REPLACES   PHASE
...
openshift-logging                                       clusterlogging.4.5.0-202007012112.p0         Cluster Logging          4.5.0-202007012112.p0              Succeeded
...

  5. Create a Cluster Logging instance:

    1. Create an instance object YAML file (for example, clo-instance.yaml) for the Cluster Logging Operator:

      注意

      This default Cluster Logging configuration should support a wide array of environments. Review the topics on tuning and configuring the Cluster Logging components for information on modifications you can make to your Cluster Logging cluster. 

      apiVersion: "logging.openshift.io/v1"
kind: "ClusterLogging"
metadata:
  name: "instance" 1
  namespace: "openshift-logging"
spec:
  managementState: "Managed"  2
  logStore:
    type: "elasticsearch"  3
    retentionPolicy: 4
      application:
        maxAge: 1d
      infra:
        maxAge: 7d
      audit:
        maxAge: 7d
    elasticsearch:
      nodeCount: 3 5
      storage:
        storageClassName: "<storage-class-name>" 6
        size: 200G
      resources: 7
        requests:
          memory: "8Gi"
      proxy: 8
        resources:
          limits:
            memory: 256Mi
          requests:
             memory: 256Mi
      redundancyPolicy: "SingleRedundancy"
  visualization:
    type: "kibana"  9
    kibana:
      replicas: 1
  curation:
    type: "curator"
    curator:
      schedule: "30 3 * * *" 10
  collection:
    logs:
      type: "fluentd"  11
      fluentd: {}
      1
      The name must be instance.
      2
      The cluster logging management state. In some cases, if you change the cluster logging defaults, you must set this to Unmanaged. However, an unmanaged deployment does not receive updates until cluster logging is placed back into a managed state. Placing a deployment back into a managed state might revert any modifications you made.
      3
      Settings for configuring Elasticsearch. Using the custom resource (CR), you can configure shard replication policy and persistent storage.
      4
      Specify the length of time that Elasticsearch should retain each log source. Enter an integer and a time designation: weeks(w), hours(h/H), minutes(m) and seconds(s). For example, 7d for seven days. Logs older than the maxAge are deleted. You must specify a retention policy for each log source or the Elasticsearch indices will not be created for that source.
      5
      Specify the number of Elasticsearch nodes. See the note that follows this list.
      6
      Enter the name of an existing storage class for Elasticsearch storage. For best performance, specify a storage class that allocates block storage. If you do not specify a storage class, OpenShift Container Platform deploys cluster logging with ephemeral storage only.
      7
      Specify the CPU and memory requests for Elasticsearch as needed. If you leave these values blank, the Elasticsearch Operator sets default values that should be sufficient for most deployments. The default values are 16G for the memory request and 1 for the CPU request.
      8
      Specify the CPU and memory requests for the Elasticsearch proxy as needed. If you leave these values blank, the Elasticsearch Operator sets default values that should be sufficient for most deployments. The default values are 256Mi for the memory request and 100m for the CPU request.
      9
      Settings for configuring Kibana. Using the CR, you can scale Kibana for redundancy and configure the CPU and memory for your Kibana pods. For more information, see Configuring the log visualizer.
      10
      Settings for configuring the Curator schedule. Curator is used to remove data that is in the Elasticsearch index format prior to OpenShift Container Platform 4.5 and will be removed in a later release.
      11
      Settings for configuring Fluentd. Using the CR, you can configure Fluentd CPU and memory limits. For more information, see Configuring Fluentd.
      注意

      The maximum number of Elasticsearch master nodes is three. If you specify a nodeCount greater than 3, OpenShift Container Platform creates three Elasticsearch nodes that are Master-eligible nodes, with the master, client, and data roles. The additional Elasticsearch nodes are created as Data-only nodes, using client and data roles. Master nodes perform cluster-wide actions such as creating or deleting an index, shard allocation, and tracking nodes. Data nodes hold the shards and perform data-related operations such as CRUD, search, and aggregations. Data-related operations are I/O-, memory-, and CPU-intensive. It is important to monitor these resources and to add more Data nodes if the current nodes are overloaded.

      For example, if nodeCount=4, the following nodes are created: 

      $ oc get deployment

      Example output

      cluster-logging-operator       1/1     1            1           18h
elasticsearch-cd-x6kdekli-1    1/1     1            0           6m54s
elasticsearch-cdm-x6kdekli-1   1/1     1            1           18h
elasticsearch-cdm-x6kdekli-2   1/1     1            0           6m49s
elasticsearch-cdm-x6kdekli-3   1/1     1            0           6m44s

      The number of primary shards for the index templates is equal to the number of Elasticsearch data nodes.

    2. Create the instance: 

      $ oc create -f <file-name>.yaml

      For example: 

      $ oc create -f clo-instance.yaml

      This creates the Cluster Logging components, the Elasticsearch custom resource and components, and the Kibana interface.

  6. Verify the installation by listing the pods in the openshift-logging project.

    You should see several pods for Cluster Logging, Elasticsearch, Fluentd, and Kibana similar to the following list: 

    $ oc get pods -n openshift-logging

    Example output

    NAME                                            READY   STATUS    RESTARTS   AGE
cluster-logging-operator-66f77ffccb-ppzbg       1/1     Running   0          7m
elasticsearch-cdm-ftuhduuw-1-ffc4b9566-q6bhp    2/2     Running   0          2m40s
elasticsearch-cdm-ftuhduuw-2-7b4994dbfc-rd2gc   2/2     Running   0          2m36s
elasticsearch-cdm-ftuhduuw-3-84b5ff7ff8-gqnm2   2/2     Running   0          2m4s
fluentd-587vb                                   1/1     Running   0          2m26s
fluentd-7mpb9                                   1/1     Running   0          2m30s
fluentd-flm6j                                   1/1     Running   0          2m33s
fluentd-gn4rn                                   1/1     Running   0          2m26s
fluentd-nlgb6                                   1/1     Running   0          2m30s
fluentd-snpkt                                   1/1     Running   0          2m28s
kibana-d6d5668c5-rppqm                          2/2     Running   0          2m39s