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Troubleshooting Guide
OpenShift Enterprise 2
Troubleshooting OpenShift Enterprise
Red Hat OpenShift Documentation Team
Abstract
The OpenShift Enterprise Troubleshooting Guide provides information on resolving common problems with OpenShift Enterprise installations. This guide provides the following information to help diagnose and fix general problems:
- Configuration of standard Linux components and corresponding log files
- Configuration of OpenShift Enterprise components and corresponding log files
- Recognizing common system problems
- Error messages that may occur when creating applications
This guide is intended for experienced system administrators.
Chapter 1. Introduction to OpenShift Enterprise
OpenShift Enterprise by Red Hat is a Platform as a Service (PaaS) that provides developers and IT organizations with an auto-scaling, cloud application platform for deploying new applications on secure, scalable resources with minimal configuration and management overhead. OpenShift Enterprise supports a wide selection of programming languages and frameworks, such as Java, Ruby, and PHP. Integrated developer tools, such as Eclipse integration, JBoss Developer Studio, and Jenkins, support the application life cycle.
Built on Red Hat Enterprise Linux, OpenShift Enterprise provides a secure and scalable multi-tenant operating system for today's enterprise-class applications while providing integrated application runtimes and libraries.
OpenShift Enterprise brings the OpenShift PaaS platform to customer data centers, enabling organizations to implement a private PaaS that meets security, privacy, compliance, and governance requirements.
1.1. What's New in Current Release
For a complete list of all the new features available in the current release of OpenShift Enterprise, see the current edition of the OpenShift Enterprise Release Notes at https://access.redhat.com/site/documentation. New features that are available in the current release are documented in the respective sections of this book.
Chapter 2. Log Files and Validation Scripts
This chapter helps you locate various log files and other information that can aid in troubleshooting some of the common issues with OpenShift Enterprise.
2.1. Configuration and Log Files for Standard Linux Components
OpenShift Enterprise uses mostly standard Linux components such as networking, httpd, SELinux, and others. Any prior administration experience with these components will be helpful in troubleshooting common issues with your OpenShift Enterprise deployment.
2.1.1. General Information
General information can be found in the
/var/log/messages file. This serves as a good starting point to investigate issues that might not be logged anywhere else.
The
/var/log/httpd/access_log file shows whether your web request was received by the host.
The
/var/log/httpd/error_log file can be helpful in troubleshooting certain problems on broker and node hosts.
The
/var/log/audit/audit.log file is useful for finding problems that might be caused by SELinux violations.
The
/var/log/secure file logs user and SSH interactions. Because users can SSH into their gears, and all Git requests also authenticate using SSH, this file is useful for checking interaction with gears on node hosts.
2.1.2. Networking
DNS
The best place for Linux operators to begin troubleshooting DNS problems on broker, node, or client hosts is the /etc/resolv.conf file. On client hosts running other operating systems, look in the appropriate network configuration file.
If your OpenShift Enterprise installation uses a BIND server, this should be listed in the
/etc/resolv.conf file as the first nameserver.
On client hosts, the first nameserver listed in the
/etc/resolv.conf file should point to your OpenShift Enterprise installation, either receiving updates from it, or delegating the domain to the nameserver of your installation.
If a hostname of your OpenShift Enterprise installation does not resolve correctly, use the following command to find the server the response is actually coming from:
# dig hostname
The application hostname is a CNAME for the node host DNS record. However, for a scaled application, this command will only show which node host contains the HAProxy gear; other gears could reside on different node hosts.
BIND
If you are running a BIND server on the broker (or supporting) host, the configuration information is contained in the /var/named/dynamic directory. The zone file syntax is domain.com.db.zone; so if the domain of your OpenShift Enterprise installation is example.com, the zone file name would be example.com.db.zone. However, not all changes will be in the zone file. Recent changes can be contained in a binary journal file.
Use the following command to view the entire zone according to the nameserver:
# dig domain axfr
DHCP
For broker and node hosts, DHCP is currently only supported if the host IPs are pinned, meaning they do not change during lease renewal. This also applies to nameservers, in that they should also not change if pinned.
If DHCP is in use, networking parameters will update at boot time, or at lease renewal. If DNS resolution on an OpenShift Enterprise host stops working after initial installation, look in the
/etc/dhcp/dhclient-network-interface.conf file to verify the nameservers provided by the DHCP service are being overwritten when a new lease is obtained.
If your configuration in the
/etc/resolv.conf file is overwritten with incorrect values, check your configuration in the dhclient-network-interface.conf file.
2.1.3. SELinux
When error messages indicate access denials but standard Linux file permissions appear to allow access, it could be due to SELinux policy. Use the following method for troubleshooting SELinux issues or verify whether the problem is SELinux related. Red Hat recommends this procedure for finding all SELinux related problems.
Procedure 2.1. To Troubleshoot SELinux Issues:
- As root, run the following command to set SELinux to permissive mode:
#
setenforce 0 - Retry the failing action. If the action succeeds then the issue is SELinux related.
- Run the following command to set SELinux back to enforcing mode:
#
setenforce 1 - Check the
/var/log/audit/audit.logfile for any SELinux violations.
This allows the offending action to proceed and log everything that otherwise would have been denied with SELinux enforced. In enforcing mode, not all denials are logged in the audit log, and the first denial generally blocks the action from proceeding to what might be further denials.
2.1.4. Control Groups on Node Hosts
Control groups (cgroups) enable you to allocate resources such as CPU time, system memory, and network bandwidth among user-defined groups of tasks (processes) running on a system. When the
cgconfig service is running correctly on a node host, you see the following:
- The
/etc/cgconfig.conffile exists with the SELinux label:system_u:object_r:cgconfig_etc_t:s0. - The
/etc/cgconfig.conffile joins CPU, cpuacct, memory, freezer, and net_cls in the/croup/alldirectory. - The
/cgroupdirectory exists, with the SELinux label:system_u:object_r:cgroup_t:s0. - The cgconfig service is running.
When the cgred service is running correctly, you see the following:
- The
/etc/cgrules.conffile exists with the SELinux label:system_u:object_r:cgrules_etc_t:s0 - The cgred service is running.
If there are gears running on the node host, you also see the following:
- A line for each gear in the
/etc/cgrules.conffile. - A directory for each gear in the
/cgroup/all/openshiftdirectory. - All processes with the gear UUID are listed in the gear's
cgroup.procsfile. This file is located in the/cgroup/all/openshift/gear_UUIDdirectory.
Important
If you created the configuration files interactively as a root user, the SELinux user label would be
unconfined_u and not system_u. For example, the SELinux label in /etc/cgconfig.conf would be unconfined_u:object_r:cgconfig_etc_t:s0.
2.1.5. Pluggable Authentication Modules
The pam_limits module controls access to system resources. Specifically, OpenShift Enterprise uses the
nproc value to control the number of processes a given account can create.
The default value for a new gear is configured in the
/etc/openshift/resource_limits.conf file on the node host:
limits_nproc=2048
When a new gear is created, a
84-gear_UUID.conf file is created on the node host, in the /etc/security/limits.d directory. Replace gear_UUID with the UNIX account name for the gear. This contains a rule set that defines the limits for that UNIX account. The first field of each line in the file is the gear UUID.
The
nproc limit for an individual gear is increased by changing the value in the 84-gear_UUID.conf file:
# PAM process limits for guest
# see limits.conf(5) for details
#Each line describes a limit for a user in the form:
#
#<domain> <type> <item> <value>
32ec916eeaa04032b1481af5037a6dfb hard nproc 250
If a gear process is failing, check the
nproc limit.
2.1.6. Disk Quotas
Verify that the mount point for the
/var/lib/openshift directory has the usrquota option enabled in the /etc/fstab file, and has been mounted. Remount the directory if necessary using the command shown below, and check the output.
# mount -o remount filesystem
Use the following command to verify that the quotas are configured correctly:
# repquota -a
2.1.7. iptables
Network firewalls are implemented with iptables. Use the following command to view the current policies:
# iptables -L
The screen outputs for the
iptables -L command for both a broker host and a node host are shown below.
iptables Policy for Broker Host
Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED ACCEPT icmp -- anywhere anywhere ACCEPT all -- anywhere anywhere ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:ssh ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:domain ACCEPT udp -- anywhere anywhere state NEW udp dpt:domain ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:https ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:http ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:61613 REJECT all -- anywhere anywhere reject-with icmp-host-prohibited Chain FORWARD (policy ACCEPT) target prot opt source destination REJECT all -- anywhere anywhere reject-with icmp-host-prohibited Chain OUTPUT (policy ACCEPT) target prot opt source destination
iptables Policy for Node Host
Chain INPUT (policy ACCEPT) target prot opt source destination ACCEPT all -- anywhere anywhere state RELATED,ESTABLISHED ACCEPT icmp -- anywhere anywhere ACCEPT all -- anywhere anywhere ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:ssh ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:https ACCEPT tcp -- anywhere anywhere state NEW tcp dpt:http ACCEPT tcp -- anywhere anywhere state NEW tcp dpts:35531:65535 REJECT all -- anywhere anywhere reject-with icmp-host-prohibited Chain FORWARD (policy ACCEPT) target prot opt source destination REJECT all -- anywhere anywhere reject-with icmp-host-prohibited Chain OUTPUT (policy ACCEPT) target prot opt source destination
2.2. Configuration and Log Files for OpenShift Components
This section provides you with the locations of various configuration and log files for OpenShift Enterprise and related components.
2.2.1. General Configuration
The
/etc/openshift directory contains the most important configuration files for OpenShift Enterprise. These configuration files correspond to the type of installation; for example, a broker host, node host, or a client host. Check the corresponding configuration file to verify that the settings are suitable for your system.
2.2.2. Broker Host Failures
In the
/var/log/openshift/broker/httpd/ directory, check the access_log and error_log files when user interactions with the broker host are failing. Verify that the request was authenticated and forwarded to the broker application.
The broker application is a Rails application, and all associated logs are saved in the
/var/log/openshift/broker/production.log file.
User actions for Rails are stored in the
/var/log/openshift/broker/user_action.log file. This log file includes gears created and deleted by a user. However, the logs do not include gear UUIDs.
2.2.3. MCollective
MCollective is used for any node host communications or interactions with either the broker host or other nodes. This can include gear placement or removal.
Use the following command to verify that a broker can communicate with all node hosts:
# oo-mco ping
broker.mydomain.com time=134.85 ms
node.mydomain.com time=541.41 ms
node1.mydomain.com time=572.76 ms
---- ping statistics ----
3 replies max: 572.76 min: 134.85 avg: 416.34
All configured node hosts should be represented in the output. If you do not see a node host as expected, verify that the network and clock settings are configured correctly for that node host.
Note
If the
oo-mco ping command is not running successfully, it could be that openshift-origin-util-scl is not properly installed on your machine, or that oo-mco ping is missing. Install the openshift-origin-util-scl package in order to run the command.
Communication between broker and node hosts is logged in the following files:
/var/log/openshift/node/ruby193-mcollective.logon node hosts/var/log/openshift/broker/ruby193-mcollective-client.logon broker hosts
Communication that is dropped due to exceeding TTL is also logged in these files.
MCollective actions performed on the node can also log more details in
/var/log/openshift/node/platform.log and /var/log/openshift/node/platform-trace.log.
If necessary, you can determine on which node host an application is created using the
dig or host command, with the application's hostname.
2.2.4. Gears
All gear information is stored in the
/var/lib/openshift directory on that gear's node host, and represented by the gear's UUID. This directory contains the following information:
- Gears themselves
- Web server configuration
- Operation directories
Use the
ls command to show the contents of the /var/lib/openshift/.httpd.d directory.
# ls /var/lib/openshift/.httpd.d/
aliases.db frontend-mod-rewrite-https-template.erb idler.db nodes.db routes.json sts.txt
aliases.txt geardb.json idler.txt nodes.txt sts.db
Gear UUIDs are also represented as users in the
/etc/passwd file.
2.3. Validation Scripts
OpenShift Enterprise includes validation scripts that detect and report potential problems with broker and node hosts. Red Hat recommends that these scripts are used for monitoring purposes when performing the initial installation. After initial installation, these scripts can help troubleshoot any OpenShift Enterprise problems. Validation scripts detect common user errors, as well as unexpected failures. See the OpenShift Enterprise Administration Guide at https://access.redhat.com/site/documentation for more information on validation scripts.
2.3.1. Broker Host Scripts
This section describes validation scripts you can use to troubleshoot issues with broker hosts.
2.3.1.1. Verifying Broker Host Configuration
Use the
oo-accept-broker script without any options to report potential problems in the broker host configuration. The output from this script indicates how many problems are found.
2.3.1.2. Fixing Gear Discrepancies
Use the
oo-admin-chk script without any options to compare gear records in the broker's Mongo datastore to the gears actually present on the node hosts. The script reports any discrepancies that are found.
Example 2.1. Diagnosing Problems Using oo-admin-chk
# oo-admin-chk
Check failed.
FAIL - user user@domain.com has a mismatch in consumed gears (-1) and actual gears (0)!
This indicates a mismatch between the number of consumed gears and the number of actual gears, which can occur under certain race conditions.
This problem can be fixed using the
oo-admin-ctl-user command:
# oo-admin-ctl-user -l user@domain.com --setconsumedgears 0
Example 2.2. Diagnosing Problems Using oo-admin-chk
# oo-admin-chk
Gear 9bb07b76dca44c3b939c9042ecf1e2fe exists on node [node1.example.com, uid:2828] but does not exist in mongo database
This output indicates that although a gear was destroyed from the broker host's MongoDB, it was not completely removed from the node host. This can be due to storage issues or other unexpected failures. You can fix this issue by deleting the gear from the /var/lib/openshift directory, and removing the user from the node host.
These are two examples of the issues that could occur when running the
oo-admin-chk script. The script should be self-explanatory to resolve most problems.
2.3.2. Node Host Scripts
This section describes validation scripts you can use to troubleshoot issues with node hosts.
2.3.2.1. Verifying Node Host Configuration
Use the
oo-accept-node script without any options to report potential problems in the node host configuration. The output from this script indicates how many problems are found.
2.3.3. Additional Diagnostics
The
oo-diagnostics script can be run on any OpenShift Enterprise host to diagnose common problems and provide potential solutions. It can also be helpful for gathering information (particularly when run with the -v option for verbose output) to provide to Red Hat Support when opening a support case.
Chapter 3. Recognizing System Problems
This chapter describes common OpenShift Enterprise system problems, and provides information to troubleshoot and resolve these issues.
3.1. Missing Repositories
If you are having issues installing the required OpenShift Enterprise software packages, verify that you have the correct YUM repositories configured. If you are using the classic RHN subscription, you must enable the correct channels. Both the broker and node host installations require a Red Hat Enterprise Linux 6 subscription.
Furthermore, each type of installation requires the designated RHN channels and repositories. Therefore, if you are installing a broker host, RHN channels and repositories that are specific to the broker host must be enabled. Similarly, repositories and RHN channels specific to the node host must be enabled when installing a node host.
The following table shows the required repositories for OpenShift Enterprise, with a brief description of each.
Table 3.1. List of Repositories
| Name of Repository | Description |
|---|---|
| Red Hat OpenShift Enterprise Infrastructure | Broker / BIND / Mongo hosts |
| Red Hat OpenShift Enterprise Application Node | Node hosts |
| Red Hat OpenShift Enterprise Client Tools | Client hosts |
| Red Hat OpenShift Enterprise JBoss EAP add-on | Included with EAP support purchase. See note below. |
| Red Hat OpenShift Enterprise Application Platform | Included with EAP support purchase. See note below. |
| Red Hat OpenShift Enterprise Web Server | Included with bundle purchase. See note below. |
Note
These repositories are required on node hosts for JBoss cartridge support.
Important
Configuring the wrong RHN channels or repositories can result in a failed installation.
3.2. Missing Node Host
When you run the
oo-mco ping command on the broker host, all node hosts should be listed in the output. Although applications on an unlisted node host can continue to operate without problems, the unlisted node hosts are not controlled by the broker host.
Node hosts may not respond to the
oo-mco ping command if the clock on the broker host is not synchronized with the clock on the node host. MCollective messages have a TTL of 60 seconds. Therefore, if the clocks are not synchronized the MCollective messages can be dropped, causing communication issues. Verify that the broker host and node host clocks are synchronized, and the ntpd service is enabled. All configured hosts must use the same NTP server.
Clock synchronization issues are logged in the
/var/log/openshift/node/ruby193-mcollective.log file on the node host, and could look like the following sample screen output:
W, [2012-08-10T14:27:01.526544 #12179] WARN -- : runner.rb:62:in `run' Message 8beea9354f9784de939ec5693940d5ce from uid=48@broker.example.com created at 1344622854 is 367 seconds old, TTL is 60
The node host also may not respond to the
oo-mco ping command if ActiveMQ on the broker host cannot communicate with MCollective on the node host. Verify that the ruby193-mcollective service is running on the node host, and it can communicate with ActiveMQ on the broker host. If a configuration has been modified recently, use the following command to restart the ruby193-mcollective service:
# service ruby193-mcollective restart
3.3. Broker Application Response Failure
The broker host service is a Rails application that runs inside the
Passenger service. There can be cases when the broker host service appears to be running, but in reality is not. If the Passenger service fails to start for some reason, the broker host service will not start, even if the httpd service is running. So even though the service openshift-broker start command reports success, the service may not actually be running.
Failures and problems with the
Passenger service are logged in the /var/www/openshift/broker/httpd/logs/error_log file on the broker host, as shown in the following screen output:
[Wed Oct 17 23:48:04 2012] [error] *** Passenger could not be initialized because of this error: Unable to start the Phusion Passenger watchdog (/usr/lib64/gems/exts/passenger-3.0.17/agents/PassengerWatchdog): Permission denied (13)
This shows that the
Passenger service has failed to start. This can be caused by dependency issues with the RubyGems package, which often occurs when Bundler attempts to regenerate the /var/www/openshift/broker/Gemfile.lock file.
Run the following commands to verify whether this problem exists:
#This shows that the specified dependency was not found. Updating all Ruby gems, and restarting thecd /var/www/openshift/broker/#bundle --localCould not find rack-1.3.0 in any of the sources
openshift-broker service could resolve this issue.
3.3.1. Missing Gems with Validation Scripts
When running validation scripts, you could also experience problems relating to
Bundler and RubyGems dependencies. This is because the validation scripts, such as oo-admin-chk, use the broker Rails configuration and also depend on the /var/www/openshift/broker/Gemfile.lock file, as shown in the following sample output:
# oo-admin-chk
Could not find rack-1.3.0 in any of the sources
Run `bundle install` to install missing gems.
Restarting the
openshift-broker service will regenerate the Gemfile.lock file, and could solve this issue. Be sure to run the yum update command before restarting the openshift-broker service.
Warning
Do not run the
bundle install command as the output asks you to do. Running this command will download and install unsupported and untested software packages, resulting in problems with your OpenShift Enterprise installation.
3.4. DNS Propagation Fails when Creating an Application
Creating an application can fail if the application's hostname cannot be resolved. This problem typically occurs if a client host in an OpenShift Enterprise deployment does not have the broker host correctly configured as a nameserver, either directly or through delegation. An example of such a failure is shown in the following sample screen output:
$ rhc app create -a myapp -t jbossas-7
Creating application: myapp in domain
Now your new domain name is being propagated (this might take a minute)...
........
retry # 3 - Waiting for DNS: myapp-domain.example.com
Eventually the process will timeout while attempting to resolve the application's hostname.
This issue can indicate that broker DNS updates are failing, or that the client host does not have the correct nameserver configured to receive DNS updates from the broker host.
This problem can also occur if the
PUBLIC_HOSTNAME setting in the /etc/openshift/node.conf file on the node host is incorrectly configured.
Note
The
oo-admin-chk script on the broker host can help detect this problem.
3.5. Developers Connecting to a Gear are Disconnected Immediately
When connecting directly to a gear, for example when a
git clone is performed, a developer can authenticate successfully, but then be disconnected by the remote host. This could be due to PAM being misconfigured. An example of this error is shown in the output below.
$ rhc app create -n apps -t php -a testing
Creating application 'testing'
==============================
Scaling: no
Gear Size: default
Cartridge: php
Namespace: apps
Password: ********
Your application's domain name is being propagated worldwide (this might take a minute)...
The authenticity of host 'testing-apps.example.com (x.x.x.x)' can't be established.
RSA key fingerprint is [...].
Are you sure you want to continue connecting (yes/no)? yes
Initialized empty Git repository in /home/test/testing/.git/
done
Error in git clone - Warning: Permanently added 'testing-apps.example.com' (RSA) to the list of known hosts.
Traceback (most recent call last):
File "/usr/bin/oo-trap-user", line 134, in <module>
read_env_vars()
File "/usr/bin/oo-trap-user", line 64, in read_env_vars
fp = open(os.path.expanduser('~/.env/') + env, 'r')
IOError: [Errno 13] Permission denied: '/var/lib/openshift/a7a330ee62ae467ca6d74cd0ce29742a/.env/OPENSHIFT_APP_NAME'
fatal: The remote end hung up unexpectedly
Ensure that PAM is correctly configured by performing the steps located in the Configuring PAM section of the OpenShift Enterprise Deployment Guide. Note that
pam_selinux should be changed to pam_openshift in /etc/pam.d/sshd, and a line with pam_namespace.so should be at the end of each file modified. If your change management system overwrote these settings, ensure that your system will retain the correctly modified files in the future.
3.6. Gears Not Idling
The
oddjob daemon must be running on node hosts for gear idling to work correctly. Error messages for gear idling issues are logged in the /var/log/httpd/error_log file on the node host. The following error message, from the error-log file, shows that the oddjob daemon is not running.
org.freedesktop.DBus.Error.ServiceUnknown: The name com.redhat.oddjob_openshift was not provided by any .service filesUse the following commands to start the
oddjob daemon, and enable it to start at boot:
#service oddjobd start#chkconfig oddjobd on
3.7. cgconfig Service Fails to Start
If the
cgconfig service fails to start, look for AVC messages in the /var/log/audit/audit.log SELinux audit log file. The error messages could indicate incorrect SELinux labels in the following files and directories:
/etc/cgconfig.conf/etc/cgrules.conf/cgroup
Use the
restorecon -v filename command to restore the correct SELinux labels for each of the files:
#This restores the correct SELinux labels in therestorecon -v /etc/cgconfig.conf#restorecon -v /etc/cgrules.conf#restorecon -rv /cgroup
/etc/cgrules.conf file.
Next, start the
cgconfig service using the following command:
# service cgconfig start
3.8. MongoDB Failures
If MongoDB is not configured correctly, you will experience failures with the OpenShift client tools. If this is the case, verify your MongoDB configuration.
Use the following command to verify that the MongoDB service is running:
# service mongod status
If the
mongod service is not running, look in the /var/log/mongodb/mongodb.log file for information. Look for duplicate configuration lines, which cause problems with MongoDB, and result in the multiple_occurences error message. Verify that there are no duplicate configuration lines in the /etc/mongodb.conf file to enable the mongod service to start.
For testing a MongoDB connection, look in the
/etc/openshift/broker.conf file for MongoDB configuration details such as database host, port, name, user, and password.
Example 3.1. Example MongoDB Configuration
MONGO_HOST_PORT="localhost:27017" MONGO_USER="mongouser" MONGO_PASSWORD="mongopassword" MONGO_DB="openshift_broker" MONGO_SSL="false"
With the
mongod service running, use the following command to connect to the database, replacing configuration settings accordingly:
# mongo localhost:27017/openshift_broker -u mongouser -p mongopassword
The MongoDB command prompt is displayed.
3.9. Jenkins Build Failures
If a gear running Jenkins is already present when the
AUTH_SALT setting is changed in the /etc/openshift/broker.conf file, subsequent Jenkins builds will initially fail with the following:
remote: Executing Jenkins build. remote: remote: You can track your build at https://jenkins-namespace.example.com/job/myapp-build remote: remote: Waiting for build to schedule........................... remote: **BUILD FAILED/CANCELLED** remote: Please see the Jenkins log for more details via rhc-tail-files remote: !!!!!!!! remote: Deployment Halted! remote: If the build failed before the deploy step, your previous remote: build is still running. Otherwise, your application may be remote: partially deployed or inaccessible. remote: Fix the build and try again. remote: !!!!!!!!Checking the Jenkins application's logs will reveal the following invalid credential messages:
# rhc tail jenkins
...
WARNING: Caught com.openshift.client.InvalidCredentialsOpenShiftException: Your credentials are not authorized to access "https://broker.example.com/broker/rest/user". Will retry 4 more times before canceling build.
com.openshift.client.InvalidCredentialsOpenShiftException: Your credentials are not authorized to access "https://broker.example.com/broker/rest/user"
...
To address these issues, first restart the broker service:
# service openshift-broker restartoo-admin-broker-auth tool to rekey the gears' authorization tokens. To rekey the tokens for all applicable gears, run the tool with the --rekey-all option:
# oo-admin-broker-auth --rekey-all--help output and man page for additional options and more detailed use cases.
When the gears are successfully rekeyed, future builds should continue as normal.
3.10. Outdated Cartridge List
If a newly installed cartridge is not immediately available, it could be due to an outdated, cached cartridge list. The first time the REST API is accessed, the broker host uses MCollective to retrieve the list of available cartridges from a node host. By default, this list is cached for six hours in a production environment. If the installed cartridges are modified, the cache must be cleared either manually, or by waiting until the cache expires before developers can access the updated list.
In addition, the Management Console has its own cached list of installed cartridges that must be cleared for any changes to be observed.
Use the following command on each broker in your OpenShift Enterprise installation to clear the broker cache only:
# oo-admin-broker-cache --clear
Use the following command on each broker in your OpenShift Enterprise installation to clear the broker and Console cache (the
--console option implies --clear):
# oo-admin-broker-cache --console
Chapter 4. Error Messages when Creating Applications
This chapter describes error messages you could encounter when creating applications on OpenShift Enterprise, and possible resolutions.
4.1. cpu.cfs_quota_us: No such file
The
rhc app create command can fail to create an application if cgroups are not working properly. These error messages are logged in the /var/log/openshift/node/ruby193-mcollective.log file on the node host, and can look like the following:
/cgroup/all/openshift/*/cpu.cfs_quota_us: No such file
See Section 2.1.4, “Control Groups on Node Hosts” for instructions on how to verify that cgroups are correctly configured.
4.2. Password Prompt
When you create a new application on OpenShift Enterprise, the client host attempts to clone the remote Git repository, which is located in the application's gear on a node host. The SSH authentication process is invoked to log in to the hostname of the application's gear, which is a newly created CNAME (alias) for the public hostname of the node host.
To successfully clone the remote Git repository of the new application,
PUBLIC_HOSTNAME must be configured correctly in the /etc/openshift/node.conf file on the node host.
Sometimes when creating an application, the process halts and you are prompted for a password, as shown in the following sample screen output:
The authenticity of host 'myapp-domain.example.com (::1)' can't be established. RSA key fingerprint is 88:49:43:d2:e9:b4:4d:84:a1:d6:8a:30:85:73:d7:7f. Are you sure you want to continue connecting (yes/no)? yes e9bdfc309bef4c13889a21ddbea45f@myapp-domain.example.com's password:
This can occur when
PUBLIC_HOSTNAME resolves to the wrong IP address. In this case, PUBLIC_HOSTNAME is set to localhost.localdomain, as shown in the sample screen output below.
PUBLIC_HOSTNAME=localhost.localdomainIn this example the application's gear CNAME is created using
localhost.localdomain as the hostname for the node host. When Git attempts to authenticate using the gear user ID and SSH key, the SSH authentication fails because the application gear does not exist on localhost.localdomain, and you are prompted for a password.
The first line of the sample screen output states that the IP address for the application's gear is
(::1), which is pointing to localhost, and is not a valid IP for an application's gear. Verify that the IP address of an application's gear is a valid IP address of the node host.
In cases where
PUBLIC_HOSTNAME fails to resolve at all as a FQDN, DNS resolution times out and the Git clone process fails.
Note
The
oo-admin-chk script on the broker host can help detect this problem.
4.3. Communication Issue after Node Host Reboot
After rebooting a node host, the
rhc app create command can fail to create an application, resulting in the following error:
An error occurred while communicating with the server. This problem may only be temporary. Check that you have correctly specified your OpenShift server 'https://broker.example.com/broker/rest/domain/domain-name/applications'.
However, when verifying MCollective connectivity,
oo-mco commands on the broker host may continue to find the rebooted node host without any issues:
# oo-mco ping
node.example.com time=170.19 ms
---- ping statistics ----
1 replies max: 170.19 min: 170.19 avg: 170.19
The application creation failure can be due to a communication issue between ActiveMQ on the broker host (or dedicated ActiveMQ broker, if applicable) and MCollective on the rebooted node host. To resolve this issue, restart the
activemq service:
# service activemq restartNote
See https://bugzilla.redhat.com/show_bug.cgi?id=1028382 for more information on this issue and the described workaround.
Chapter 5. Debugging Problems with Specific Applications
5.1. Common Resources
If you are having problems with an application gear, look in the
/etc/passwd file for information unique to that particular gear. You will see an account for the gear, represented with the gear's UUID. This file also provides the path to the login shell for the application's gear. The following sample screen output shows how gears are represented in the /etc/passwd file.
........ haproxy:x:188:188::/var/lib/haproxy:/sbin/nologin postgres:x:26:26:PostgreSQL Server:/var/lib/pgsql:/bin/bash mysql:x:27:27:MySQL Server:/var/lib/mysql:/bin/bash jenkins:x:498:498:Jenkins Continuous Build server:/var/lib/jenkins:/bin/false def4330dff68444b96846dd225a0a617:x:500:500:OpenShift guest:/var/lib/openshift/def4330dff68444b96846dd225a0a617:/usr/bin/oo-trap-user c9279521cffd4a5ba1118f1b6ac2d6d6:x:500:500:OpenShift guest:/var/lib/openshift/def4330dff68444b96846dd225a0a617:/usr/bin/oo-trap-user e16a4a4c2c1144c3815f19ba36ea9d32:x:500:500:OpenShift guest:/var/lib/openshift/def4330dff68444b96846dd225a0a617:/usr/bin/oo-trap-user
Below is a list of directories and log files to help you diagnose problems with specific applications:
- The
/var/lib/openshift/gear_UUIDdirectory on the node host is the home directory for each application gear. Check the SELinux contexts. - The
/var/lib/openshift/.httpd.d/gear_UUID*directory on the node host is the operations directory for each application gear. It contains thehttpdconfiguration for that particular application gear. - The
/var/logdirectory on the node host contains theruby193-mcollective.logfile. - Searching the
/var/log/openshiftdirectory on the node host for the gear's user UUID usinggrepcould help you find problems with application gears that generate error messages. - The
/var/log/openshift/user_action.logfile on the broker host contains logs of user actions.
5.2. Rails Applications
When debugging Rails applications, do not run the Rails console as
root as some OpenShift API calls are cached under /var/www/openshift/broker/tmp/cache and are owned by the user who runs the console. When the cache expires, the broker attempts to invalidate the cache. Since the broker runs as the apache user it is unable to clear the root-owned files and returns 500 errors.
To avoid this problem, run the Rails console as the
apache user:
#su --shell=/bin/bash -l apache$cd /var/www/openshift/console$./script/rails console production
Chapter 6. Technical Support
This chapter describes how to get technical support, report bugs, and participate in the development for OpenShift Enterprise.
6.1. Reporting Bugs
If you think you have experienced a bug in your OpenShift Enterprise installation, you are encouraged to contact a support representative before you file a bug report. This will help us identify whether the bug is valid so that it receives the proper attention, and it will also ensure that a workaround or a fix is issued in a timely manner.
If you believe the bug is valid, or it has been verified to be valid, use Bugzilla to report the bug, using OpenShift Enterprise as the product name.
6.2. Getting Help
As an administrator for a supported OpenShift Enterprise installation, you can contact Red Hat technical support for assistance. Install the
sos RPM, and use the following command to create an archive of relevant host information to include with your support request.
# sosreport
Report the problems for review by OpenShift Enterprise engineers.
All OpenShift Enterprise users are invited and encouraged to participate in community support by watching and posting to the OpenShift forums. You can also join the #openshift IRC channel, on irc.freenode.net.
6.3. Participating in Development
OpenShift Origin serves as the upstream open source project for OpenShift Enterprise, and you are invited to get involved in the ongoing development.
If you have a bug fix, or would like to implement a feature, submit a pull request to include your change for release. The OpenShift repositories are located on GitHub, with the origin-server of main interest to OpenShift administrators. Your submissions could be incorporated into the OpenShift Enterprise product either individually as required, or with a subsequent release.
Appendix A. Revision History
| Revision History | ||||||
|---|---|---|---|---|---|---|
| Revision 2.1-1 | Wed Jun 11 2014 | Bilhar Aulakh | ||||
| ||||||
| Revision 2.1-0 | Fri May 16 2014 | Julie Wu | ||||
| ||||||
| Revision 2.0-1 | Tue Jan 14 2014 | Brice Fallon-Freeman | ||||
| ||||||
| Revision 2.0-0 | Tue Dec 10 2013 | Bilhar Aulakh | ||||
| ||||||
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