Using Images

If the DocumentRoot of the application is nested in the source directory /opt/openshift/src, you can provide your own .htaccess file to override the default Apache behavior and specify how application requests should be handled. The .htaccess file must be located at the root of the application source.

The first time you use the shared volume, the database is created along with the database administrator user and the MySQL root user (if you specify the MYSQL_ROOT_PASSWORD environment variable). Afterwards, the MySQL daemon starts up. If you are re-attaching the volume to another container, then the database, database user, and the administrator user are not created, and the MySQL daemon starts.

The following command creates a new database pod with MySQL running in a container:

$ oc new-app \
    -e MYSQL_USER=<username> \
    -e MYSQL_PASSWORD=<password> \
    -e MYSQL_DATABASE=<database_name> \
    registry.access.redhat.com/rhscl/mysql-56-rhel7

OpenShift Container Platform uses Software Collections (SCLs) to install and launch MySQL. If you want to execute a MySQL command inside of a running container (for debugging), you must invoke it using bash.

To do so, first identify the name of the pod. For example, you can view the list of pods in your current project:

$ oc get pods

Then, open a remote shell session to the pod:

$ oc rsh <pod>

When you enter the container, the required SCL is automatically enabled.

You can now run the mysql command from the bash shell to start a MySQL interactive session and perform normal MySQL operations. For example, to authenticate as the database user:

bash-4.2$ mysql -u $MYSQL_USER -p$MYSQL_PASSWORD -h $HOSTNAME $MYSQL_DATABASE
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.6.37 MySQL Community Server (GPL)
...
mysql>

When you are finished, enter quit or exit to leave the MySQL session.

The MySQL user name, password, and database name must be configured with the following environment variables:

MySQL settings can be configured with the following environment variables:

Some of the memory-related parameters have two default values. The fixed value is used when a container does not have memory limits assigned. The other value is calculated dynamically during a container’s startup based on available memory.

The MySQL image can be run with mounted volumes to enable persistent storage for the database:

Passwords are part of the image configuration, therefore the only supported method to change passwords for the database user (MYSQL_USER) and root user is by changing the environment variables MYSQL_PASSWORD and MYSQL_ROOT_PASSWORD, respectively.

You can view the current passwords by viewing the pod or deployment configuration in the web console or by listing the environment variables with the CLI:

$ oc set env pod <pod_name> --list

Whenever MYSQL_ROOT_PASSWORD is set, it enables remote access for the root user with the given password, and whenever it is unset, remote access for the root user is disabled. This does not affect the regular user MYSQL_USER, who always has remote access. This also does not affect local access by the root user, who can always log in without a password in localhost.

Changing database passwords through SQL statements or any way other than through the environment variables aforementioned causes a mismatch between the values stored in the variables and the actual passwords. Whenever a database container starts, it resets the passwords to the values stored in the environment variables.

To change these passwords, update one or both of the desired environment variables for the related deployment configuration(s) using the oc set env command. If multiple deployment configurations utilize these environment variables, for example in the case of an application created from a template, you must update the variables on each deployment configuration so that the passwords are in sync everywhere. This can be done all in the same command:

$ oc set env dc <dc_name> [<dc_name_2> ...] \
  MYSQL_PASSWORD=<new_password> \
  MYSQL_ROOT_PASSWORD=<new_root_password>

Updating the environment variables triggers the redeployment of the database server if you have a configuration change trigger. Otherwise, you must manually start a new deployment in order to apply the password changes.

To verify that new passwords are in effect, first open a remote shell session to the running MySQL pod:

$ oc rsh <pod>

From the bash shell, verify the database user’s new password:

bash-4.2$ mysql -u $MYSQL_USER -p<new_password> -h $HOSTNAME $MYSQL_DATABASE -te "SELECT * FROM (SELECT database()) db CROSS JOIN (SELECT user()) u"

If the password was changed correctly, you should see a table like this:

+------------+---------------------+
| database() | user()              |
+------------+---------------------+
| sampledb   | user0PG@172.17.42.1 |
+------------+---------------------+

To verify the root user’s new password:

bash-4.2$ mysql -u root -p<new_root_password> -h $HOSTNAME $MYSQL_DATABASE -te "SELECT * FROM (SELECT database()) db CROSS JOIN (SELECT user()) u"

If the password was changed correctly, you should see a table like this:

+------------+------------------+
| database() | user()           |
+------------+------------------+
| sampledb   | root@172.17.42.1 |
+------------+------------------+

To set up MySQL replication, a deployment configuration is defined in the example template that defines a replication controller. For MySQL master-slave replication, two deployment configurations are needed. One deployment configuration defines the MySQL master server and second the MySQL slave servers.

To tell a MySQL server to act as the master, the command field in the container’s definition in the deployment configuration must be set to run-mysqld-master. This script acts as an alternative entrypoint for the MySQL image and configures the MySQL server to run as the master in replication.

MySQL replication requires a special user that relays data between the master and slaves. The following environment variables are defined in the template for this purpose:

kind: "DeploymentConfig"
apiVersion: "v1"
metadata:
  name: "mysql-master"
spec:
  strategy:
    type: "Recreate"
  triggers:
    - type: "ConfigChange"
  replicas: 1
  selector:
    name: "mysql-master"
  template:
    metadata:
      labels:
        name: "mysql-master"
    spec:
      volumes:
        - name: "mysql-master-data"
          persistentVolumeClaim:
            claimName: "mysql-master"
      containers:
        - name: "server"
          image: "openshift/mysql-56-centos7"
          command:
            - "run-mysqld-master"
          ports:
            - containerPort: 3306
              protocol: "TCP"
          env:
            - name: "MYSQL_MASTER_USER"
              value: "${MYSQL_MASTER_USER}"
            - name: "MYSQL_MASTER_PASSWORD"
              value: "${MYSQL_MASTER_PASSWORD}"
            - name: "MYSQL_USER"
              value: "${MYSQL_USER}"
            - name: "MYSQL_PASSWORD"
              value: "${MYSQL_PASSWORD}"
            - name: "MYSQL_DATABASE"
              value: "${MYSQL_DATABASE}"
            - name: "MYSQL_ROOT_PASSWORD"
              value: "${MYSQL_ROOT_PASSWORD}"
          volumeMounts:
            - name: "mysql-master-data"
              mountPath: "/var/lib/mysql/data"
          resources: {}
          terminationMessagePath: "/dev/termination-log"
          imagePullPolicy: "IfNotPresent"
          securityContext:
            capabilities: {}
            privileged: false
      restartPolicy: "Always"
      dnsPolicy: "ClusterFirst"

Since we claimed a persistent volume in this deployment configuration to have all data persisted for the MySQL master server, you must ask your cluster administrator to create a persistent volume that you can claim the storage from.

After the deployment configuration is created and the pod with MySQL master server is started, it will create the database defined by MYSQL_DATABASE and configure the server to replicate this database to slaves.

The example provided defines only one replica of the MySQL master server. This causes OpenShift Container Platform to start only one instance of the server. Multiple instances (multi-master) is not supported and therefore you can not scale this replication controller.

To replicate the database created by the MySQL master, a deployment configuration is defined in the template. This deployment configuration creates a replication controller that launches the MySQL image with the command field set to run-mysqld-slave. This alternative entrypoints skips the initialization of the database and configures the MySQL server to connect to the mysql-master service, which is also defined in example template.

kind: "DeploymentConfig"
apiVersion: "v1"
metadata:
  name: "mysql-slave"
spec:
  strategy:
    type: "Recreate"
  triggers:
    - type: "ConfigChange"
  replicas: 1
  selector:
    name: "mysql-slave"
  template:
    metadata:
      labels:
        name: "mysql-slave"
    spec:
      containers:
        - name: "server"
          image: "openshift/mysql-56-centos7"
          command:
            - "run-mysqld-slave"
          ports:
            - containerPort: 3306
              protocol: "TCP"
          env:
            - name: "MYSQL_MASTER_USER"
              value: "${MYSQL_MASTER_USER}"
            - name: "MYSQL_MASTER_PASSWORD"
              value: "${MYSQL_MASTER_PASSWORD}"
            - name: "MYSQL_DATABASE"
              value: "${MYSQL_DATABASE}"
          resources: {}
          terminationMessagePath: "/dev/termination-log"
          imagePullPolicy: "IfNotPresent"
          securityContext:
            capabilities: {}
            privileged: false
      restartPolicy: "Always"
      dnsPolicy: "ClusterFirst"

This example deployment configuration starts the replication controller with the initial number of replicas set to 1. You can scale this replication controller in both directions, up to the resources capacity of your account.

The pods created by the MySQL slave replication controller must reach the MySQL master server in order to register for replication. The example template defines a headless service named mysql-master for this purpose. This service is not used only for replication, but the clients can also send the queries to mysql-master:3306 as the MySQL host.

To have a headless service, the clusterIP parameter in the service definition is set to None. Then you can use a DNS query to get a list of the pod IP addresses that represents the current endpoints for this service.

kind: "Service"
apiVersion: "v1"
metadata:
  name: "mysql-master"
  labels:
    name: "mysql-master"
spec:
  ports:
    - protocol: "TCP"
      port: 3306
      targetPort: 3306
      nodePort: 0
  selector:
    name: "mysql-master"
  clusterIP: "None"
  type: "ClusterIP"
  sessionAffinity: "None"
status:
  loadBalancer: {}

To increase the number of members in the cluster:

$ oc scale rc mysql-slave-1 --replicas=<number>

This tells the replication controller to create a new MySQL slave pod. When a new slave is created, the slave entrypoint first attempts to contact the mysql-master service and register itself to the replication set. Once that is done, the MySQL master server sends the slave the replicated database.

When scaling down, the MySQL slave is shut down and, because the slave does not have any persistent storage defined, all data on the slave is lost. The MySQL master server then discovers that the slave is not reachable anymore, and it automatically removes it from the replication.

151113  5:06:56 InnoDB: Using Linux native AIO
151113  5:06:56  InnoDB: Warning: io_setup() failed with EAGAIN. Will make 5 attempts before giving up.
InnoDB: Warning: io_setup() attempt 1 failed.
InnoDB: Warning: io_setup() attempt 2 failed.
Waiting for MySQL to start ...
InnoDB: Warning: io_setup() attempt 3 failed.
InnoDB: Warning: io_setup() attempt 4 failed.
Waiting for MySQL to start ...
InnoDB: Warning: io_setup() attempt 5 failed.
151113  5:06:59  InnoDB: Error: io_setup() failed with EAGAIN after 5 attempts.
InnoDB: You can disable Linux Native AIO by setting innodb_use_native_aio = 0 in my.cnf
151113  5:06:59 InnoDB: Fatal error: cannot initialize AIO sub-system
151113  5:06:59 [ERROR] Plugin 'InnoDB' init function returned error.
151113  5:06:59 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
151113  5:06:59 [ERROR] Unknown/unsupported storage engine: InnoDB
151113  5:06:59 [ERROR] Aborting

Alternatively, increase the aio-max-nr kernel resource. The following example examines the current value of aio-max-nr and doubles it.

$ sysctl fs.aio-max-nr
fs.aio-max-nr = 1048576
# sysctl -w fs.aio-max-nr=2097152

This is a per-node resolution and lasts until the next node reboot.

The first time you use the shared volume, the database is created along with the database administrator user and the PostgreSQL postgres user (if you specify the POSTGRESQL_ADMIN_PASSWORD environment variable). Afterwards, the PostgreSQL daemon starts up. If you are re-attaching the volume to another container, then the database, the database user, and the administrator user are not created, and the PostgreSQL daemon starts.

The following command creates a new database pod with PostgreSQL running in a container:

$ oc new-app \
    -e POSTGRESQL_USER=<username> \
    -e POSTGRESQL_PASSWORD=<password> \
    -e POSTGRESQL_DATABASE=<database_name> \
    registry.access.redhat.com/rhscl/postgresql-95-rhel7

OpenShift Container Platform uses Software Collections (SCLs) to install and launch PostgreSQL. If you want to execute a PostgreSQL command inside of a running container (for debugging), you must invoke it using bash.

To do so, first identify the name of the running PostgreSQL pod. For example, you can view the list of pods in your current project:

$ oc get pods

Then, open a remote shell session to the desired pod:

$ oc rsh <pod>

When you enter the container, the required SCL is automatically enabled.

You can now run the psql command from the bash shell to start a PostgreSQL interactive session and perform normal PostgreSQL operations. For example, to authenticate as the database user:

bash-4.2$ PGPASSWORD=$POSTGRESQL_PASSWORD psql -h postgresql $POSTGRESQL_DATABASE $POSTGRESQL_USER
psql (9.5.16)
Type "help" for help.

default=>

When you are finished, enter \q to leave the PostgreSQL session.

The PostgreSQL user name, password, and database name must be configured with the following environment variables:

PostgreSQL settings can be configured with the following environment variables:

The PostgreSQL image can be run with mounted volumes to enable persistent storage for the database:

Passwords are part of the image configuration, therefore the only supported method to change passwords for the database user (POSTGRESQL_USER) and postgres administrator user is by changing the environment variables POSTGRESQL_PASSWORD and POSTGRESQL_ADMIN_PASSWORD, respectively.

You can view the current passwords by viewing the pod or deployment configuration in the web console or by listing the environment variables with the CLI:

$ oc set env pod <pod_name> --list

Changing database passwords through SQL statements or any way other than through the environment variables aforementioned will cause a mismatch between the values stored in the variables and the actual passwords. Whenever a database container starts, it resets the passwords to the values stored in the environment variables.

To change these passwords, update one or both of the desired environment variables for the related deployment configuration(s) using the oc set env command. If multiple deployment configurations utilize these environment variables, for example in the case of an application created from a template, you must update the variables on each deployment configuration so that the passwords are in sync everywhere. This can be done all in the same command:

$ oc set env dc <dc_name> [<dc_name_2> ...] \
  POSTGRESQL_PASSWORD=<new_password> \
  POSTGRESQL_ADMIN_PASSWORD=<new_admin_password>

Updating the environment variables triggers the redeployment of the database server if you have a configuration change trigger. Otherwise, you must manually start a new deployment in order to apply the password changes.

To verify that new passwords are in effect, first open a remote shell session to the running PostgreSQL pod:

$ oc rsh <pod>

From the bash shell, verify the database user’s new password:

bash-4.2$ PGPASSWORD=<new_password> psql -h postgresql $POSTGRESQL_DATABASE $POSTGRESQL_USER -c "SELECT * FROM (SELECT current_database()) cdb CROSS JOIN (SELECT current_user) cu"

If the password was changed correctly, you should see a table like this:

 current_database | current_user
------------------+--------------
 default          | django
(1 row)

From the bash shell, verify the postgres administrator user’s new password:

bash-4.2$ PGPASSWORD=<new_admin_password> psql -h postgresql $POSTGRESQL_DATABASE postgres -c "SELECT * FROM (SELECT current_database()) cdb CROSS JOIN (SELECT current_user) cu"

If the password was changed correctly, you should see a table like this:

 current_database | current_user
------------------+--------------
 default          | postgres
(1 row)

You can configure MongoDB with an ephemeral volume or a persistent volume. The first time you use the volume, the database is created along with the database administrator user. Afterwards, the MongoDB daemon starts up. If you are re-attaching the volume to another container, then the database, database user, and the administrator user are not created, and the MongoDB daemon starts.

The following command creates a new database pod with MongoDB running in a container with an ephemeral volume:

$ oc new-app \
    -e MONGODB_USER=<username> \
    -e MONGODB_PASSWORD=<password> \
    -e MONGODB_DATABASE=<database_name> \
    -e MONGODB_ADMIN_PASSWORD=<admin_password> \
    registry.access.redhat.com/rhscl/mongodb-26-rhel7

OpenShift Container Platform uses Software Collections (SCLs) to install and launch MongoDB. If you want to execute a MongoDB command inside of a running container (for debugging), you must invoke it using bash.

To do so, first identify the name of the running MongoDB pod. For example, you can view the list of pods in your current project:

$ oc get pods

Then, open a remote shell session to the desired pod:

$ oc rsh <pod>

When you enter the container, the required SCL is automatically enabled.

You can now run mongo commands from the bash shell to start a MongoDB interactive session and perform normal MongoDB operations. For example, to switch to the sampledb database and authenticate as the database user:

bash-4.2$ mongo -u $MONGODB_USER -p $MONGODB_PASSWORD $MONGODB_DATABASE
MongoDB shell version: 2.6.9
connecting to: sampledb
>

When you are finished, press CTRL+D to leave the MongoDB session.

The MongoDB user name, password, database name, and admin password must be configured with the following environment variables:

MongoDB settings can be configured with the following environment variables:

The MongoDB image can be run with mounted volumes to enable persistent storage for the database:

Passwords are part of the image configuration, therefore the only supported method to change passwords for the database user (MONGODB_USER) and admin user is by changing the environment variables MONGODB_PASSWORD and MONGODB_ADMIN_PASSWORD, respectively.

You can view the current passwords by viewing the pod or deployment configuration in the web console or by listing the environment variables with the CLI:

$ oc set env pod <pod_name> --list

Changing database passwords directly in MongoDB causes a mismatch between the values stored in the variables and the actual passwords. Whenever a database container starts, it resets the passwords to the values stored in the environment variables.

To change these passwords, update one or both of the desired environment variables for the related deployment configuration(s) using the oc set env command. If multiple deployment configurations utilize these environment variables, for example in the case of an application created from a template, you must update the variables on each deployment configuration so that the passwords are in sync everywhere. This can be done all in the same command:

$ oc set env dc <dc_name> [<dc_name_2> ...] \
  MONGODB_PASSWORD=<new_password> \
  MONGODB_ADMIN_PASSWORD=<new_admin_password>

Updating the environment variables triggers the redeployment of the database server if you have a configuration change trigger. Otherwise, you must manually start a new deployment in order to apply the password changes.

To verify that new passwords are in effect, first open a remote shell session to the running MongoDB pod:

$ oc rsh <pod>

From the bash shell, verify the database user’s new password:

bash-4.2$ mongo -u $MONGODB_USER -p <new_password> $MONGODB_DATABASE --eval "db.version()"

If the password was changed correctly, you should see output like this:

MongoDB shell version: 2.6.9
connecting to: sampledb
2.6.9

To verify the admin user’s new password:

bash-4.2$ mongo -u admin -p <new_admin_password> admin --eval "db.version()"

If the password was changed correctly, you should see output like this:

MongoDB shell version: 2.6.9
connecting to: admin
2.6.9

Assuming you already have three pre-created persistent volumes or configured persistent volume provisioning.

After creating a cluster from the example template, you have a replica set with three members. Once the pods are running you can perform various actions on these pods such as:

MongoDB recommends an odd number of members in a replica set. If there are sufficient available persistent volumes, or a dynamic storage provisioner is present, scaling up is done by using the oc scale command:

$ oc scale --replicas=5 statefulsets/mongodb

$ oc get pods
NAME        READY     STATUS    RESTARTS   AGE
mongodb-0   1/1       Running   0          9m
mongodb-1   1/1       Running   0          8m
mongodb-2   1/1       Running   0          8m
mongodb-3   1/1       Running   0          1m
mongodb-4   1/1       Running   0          57s

This creates new pods which connect to the replica set and updates its configuration.

To scale down a replica set it is possible to go from five to three members, or from three to only one member.

Although scaling up may be done without manual intervention when the preconditions are met (storage availability, size of existing database and oplogSize), scaling down always require manual intervention.

To scale down:

The first time you use the shared volume, the database is created along with the database administrator user and the MariaDB root user (if you specify the MYSQL_ROOT_PASSWORD environment variable). Afterwards, the MariaDB daemon starts up. If you are re-attaching the volume to another container, then the database, database user, and the administrator user are not created, and the MariaDB daemon starts.

The following command creates a new database pod with MariaDB running in a container:

$ oc new-app \
    -e MYSQL_USER=<username> \
    -e MYSQL_PASSWORD=<password> \
    -e MYSQL_DATABASE=<database_name> \
    registry.access.redhat.com/rhscl/mariadb-101-rhel7

OpenShift Container Platform uses Software Collections (SCLs) to install and launch MariaDB. If you want to execute a MariaDB command inside of a running container (for debugging), you must invoke it using bash.

To do so, first identify the name of the running MariaDB pod. For example, you can view the list of pods in your current project:

$ oc get pods

Then, open a remote shell session to the pod:

$ oc rsh <pod>

When you enter the container, the required SCL is automatically enabled.

You can now run mysql commands from the bash shell to start a MariaDB interactive session and perform normal MariaDB operations. For example, to authenticate as the database user:

bash-4.2$ mysql -u $MYSQL_USER -p$MYSQL_PASSWORD -h $HOSTNAME $MYSQL_DATABASE
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 4
Server version: 5.5.37 MySQL Community Server (GPL)
...
mysql>

When you are finished, enter quit or exit to leave the MySQL session.

The MariaDB user name, password, and database name must be configured with the following environment variables:

MariaDB settings can be configured with the following environment variables:

The MariaDB image can be run with mounted volumes to enable persistent storage for the database:

Passwords are part of the image configuration, therefore the only supported method to change passwords for the database user (MYSQL_USER) and admin user is by changing the environment variables MYSQL_PASSWORD and MYSQL_ROOT_PASSWORD, respectively.

You can view the current passwords by viewing the pod or deployment configuration in the web console or by listing the environment variables with the CLI:

$ oc set env pod <pod_name> --list

Changing database passwords through SQL statements or any way other than through the environment variables aforementioned causes a mismatch between the values stored in the variables and the actual passwords. Whenever a database container starts, it resets the passwords to the values stored in the environment variables.

To change these passwords, update one or both of the desired environment variables for the related deployment configuration(s) using the oc set env command. If multiple deployment configurations utilize these environment variables, for example in the case of an application created from a template, you must update the variables on each deployment configuration so that the passwords are in sync everywhere. This can be done all in the same command:

$ oc set env dc <dc_name> [<dc_name_2> ...] \
  MYSQL_PASSWORD=<new_password> \
  MYSQL_ROOT_PASSWORD=<new_root_password>

Updating the environment variables triggers the redeployment of the database server if you have a configuration change trigger. Otherwise, you must manually start a new deployment in order to apply the password changes.

To verify that new passwords are in effect, first open a remote shell session to the running MariaDB pod:

$ oc rsh <pod>

From the bash shell, verify the database user’s new password:

bash-4.2$ mysql -u $MYSQL_USER -p<new_password> -h $HOSTNAME $MYSQL_DATABASE -te "SELECT * FROM (SELECT database()) db CROSS JOIN (SELECT user()) u"

If the password was changed correctly, you should see a table like this:

+------------+---------------------+
| database() | user()              |
+------------+---------------------+
| sampledb   | user0PG@172.17.42.1 |
+------------+---------------------+

To verify the root user’s new password:

bash-4.2$ mysql -u root -p<new_root_password> -h $HOSTNAME $MYSQL_DATABASE -te "SELECT * FROM (SELECT database()) db CROSS JOIN (SELECT user()) u"

If the password was changed correctly, you should see a table like this:

+------------+------------------+
| database() | user()           |
+------------+------------------+
| sampledb   | root@172.17.42.1 |
+------------+------------------+

151113  5:06:56 InnoDB: Using Linux native AIO
151113  5:06:56  InnoDB: Warning: io_setup() failed with EAGAIN. Will make 5 attempts before giving up.
InnoDB: Warning: io_setup() attempt 1 failed.
InnoDB: Warning: io_setup() attempt 2 failed.
Waiting for MySQL to start ...
InnoDB: Warning: io_setup() attempt 3 failed.
InnoDB: Warning: io_setup() attempt 4 failed.
Waiting for MySQL to start ...
InnoDB: Warning: io_setup() attempt 5 failed.
151113  5:06:59  InnoDB: Error: io_setup() failed with EAGAIN after 5 attempts.
InnoDB: You can disable Linux Native AIO by setting innodb_use_native_aio = 0 in my.cnf
151113  5:06:59 InnoDB: Fatal error: cannot initialize AIO sub-system
151113  5:06:59 [ERROR] Plugin 'InnoDB' init function returned error.
151113  5:06:59 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
151113  5:06:59 [ERROR] Unknown/unsupported storage engine: InnoDB
151113  5:06:59 [ERROR] Aborting

Alternatively, increase the aio-max-nr kernel resource. The following example examines the current value of aio-max-nr and doubles it.

$ sysctl fs.aio-max-nr
fs.aio-max-nr = 1048576
# sysctl -w fs.aio-max-nr=2097152

This is a per-node resolution and lasts until the next node reboot.

You can manage Jenkins authentication in two ways:

$ oc new-app -e \
    JENKINS_PASSWORD=<password> \
    openshift/jenkins-2-centos7

The Jenkins server can be configured with the following environment variables:

If you are going to run Jenkins somewhere other than as a deployment within your same project, you will need to provide an access token to Jenkins to access your project.

The token field contains the token value Jenkins needs to access the project.

The Jenkins image can be run with mounted volumes to enable persistent storage for the configuration:

To customize the official OpenShift Container Platform Jenkins image, you have two options:

You can use S2I to copy your custom Jenkins Jobs definitions, additional plug-ins or replace the provided config.xml file with your own, custom, configuration.

In order to include your modifications in the Jenkins image, you need to have a Git repository with the following directory structure:

pluginId:pluginVersion

The contents of the configuration/ directory will be copied into the /var/lib/jenkins/ directory, so you can also include additional files, such as credentials.xml, there.

The following is an example build configuration that customizes the Jenkins image in OpenShift Container Platform:

apiVersion: v1
kind: BuildConfig
metadata:
  name: custom-jenkins-build
spec:
  source:                       1
    git:
      uri: https://github.com/custom/repository
    type: Git
  strategy:                     2
    sourceStrategy:
      from:
        kind: ImageStreamTag
        name: jenkins:latest
        namespace: openshift
    type: Source
  output:                       3
    to:
      kind: ImageStreamTag
      name: custom-jenkins:latest

The OpenShift Container Platform Jenkins image includes the pre-installed Kubernetes plug-in that allows Jenkins slaves to be dynamically provisioned on multiple container hosts using Kubernetes and OpenShift Container Platform.

To use the Kubernetes plug-in, OpenShift Container Platform provides three images suitable for use as Jenkins slaves: the Base, Maven, and Node.js images. See Jenkins Slaves for more information.

Both the Maven and Node.js slave images are automatically configured as Kubernetes Pod Template images within the OpenShift Container Platform Jenkins image’s configuration for the Kubernetes plug-in. That configuration includes labels for each of the images that can be applied to any of your Jenkins jobs under their "Restrict where this project can be run" setting. If the label is applied, execution of the given job will be done under an OpenShift Container Platform pod running the respective slave image.

The Jenkins image also provides auto-discovery and auto-configuration of additional slave images for the Kubernetes plug-in. With the OpenShift Sync plug-in, the Jenkins image on Jenkins start-up searches within the project that it is running, or the projects specifically listed in the plug-in’s configuration for the following:

When it finds an image stream with the appropriate label, or image stream tag with the appropriate annotation, it generates the corresponding Kubernetes plug-in configuration so you can assign your Jenkins jobs to run in a pod running the container image provided by the image stream.

The name and image references of the image stream or image stream tag are mapped to the name and image fields in the Kubernetes plug-in pod template. You can control the label field of the Kubernetes plug-in pod template by setting an annotation on the image stream or image stream tag object with the key slave-label. Otherwise, the name is used as the label.

When it finds a ConfigMap with the appropriate label, it assumes that any values in the key-value data payload of the ConfigMap contains XML consistent with the config format for Jenkins and the Kubernetes plug-in pod templates. A key differentiator to note when using ConfigMaps, instead of image streams or image stream tags, is that you can control all the various fields of the Kubernetes plug-in pod template.

The following is an example ConfigMap:

kind: ConfigMap
apiVersion: v1
metadata:
  name: jenkins-slave
  labels:
    role: jenkins-slave
data:
  template1: |-
    <org.csanchez.jenkins.plugins.kubernetes.PodTemplate>
      <inheritFrom></inheritFrom>
      <name>template1</name>
      <instanceCap>2147483647</instanceCap>
      <idleMinutes>0</idleMinutes>
      <label>template1</label>
      <serviceAccount>jenkins</serviceAccount>
      <nodeSelector></nodeSelector>
      <volumes/>
      <containers>
        <org.csanchez.jenkins.plugins.kubernetes.ContainerTemplate>
          <name>jnlp</name>
          <image>openshift/jenkins-slave-maven-centos7:v3.9</image>
          <privileged>false</privileged>
          <alwaysPullImage>true</alwaysPullImage>
          <workingDir>/tmp</workingDir>
          <command></command>
          <args>${computer.jnlpmac} ${computer.name}</args>
          <ttyEnabled>false</ttyEnabled>
          <resourceRequestCpu></resourceRequestCpu>
          <resourceRequestMemory></resourceRequestMemory>
          <resourceLimitCpu></resourceLimitCpu>
          <resourceLimitMemory></resourceLimitMemory>
          <envVars/>
        </org.csanchez.jenkins.plugins.kubernetes.ContainerTemplate>
      </containers>
      <envVars/>
      <annotations/>
      <imagePullSecrets/>
      <nodeProperties/>
    </org.csanchez.jenkins.plugins.kubernetes.PodTemplate>

After startup, the OpenShift Sync plug-in monitors the API server of OpenShift Container Platform for updates to ImageStreams, ImageStreamTags, and ConfigMaps and adjusts the configuration of the Kubernetes plug-in.

In particular, the following rules will apply:

To use a container image as a Jenkins slave, the image must run the slave agent as an entrypoint. For more details about this, refer to the official Jenkins documentation.

Templates provide parameter fields to define all the environment variables (password) with predefined defaults. OpenShift Container Platform provides templates to make creating a new Jenkins service easy. The Jenkins templates should have been registered in the default openshift project by your cluster administrator during the initial cluster setup. See Loading the Default Image Streams and Templates for more details, if required.

a deployment configuration and a service.

must instantiate the template to be able to use Jenkins:

A fuller sample which achieves a similar goal is available here.

kind: List
apiVersion: v1
items:
- kind: ImageStream
  apiVersion: v1
  metadata:
    name: openshift-jee-sample
- kind: BuildConfig
  apiVersion: v1
  metadata:
    name: openshift-jee-sample-docker
  spec:
    strategy:
      type: Docker
    source:
      type: Docker
      dockerfile: |-
        FROM openshift/wildfly-101-centos7:latest
        COPY ROOT.war /wildfly/standalone/deployments/ROOT.war
        CMD $STI_SCRIPTS_PATH/run
      binary:
        asFile: ROOT.war
    output:
      to:
        kind: ImageStreamTag
        name: openshift-jee-sample:latest
- kind: BuildConfig
  apiVersion: v1
  metadata:
    name: openshift-jee-sample
  spec:
    strategy:
      type: JenkinsPipeline
      jenkinsPipelineStrategy:
        jenkinsfile: |-
          node("maven") {
            sh "git clone https://github.com/openshift/openshift-jee-sample.git ."
            sh "mvn -B -Popenshift package"
            sh "oc start-build -F openshift-jee-sample-docker --from-file=target/ROOT.war"
          }
    triggers:
    - type: ConfigChange

It is also possible to override the specification of the dynamically created Jenkins slave Pod. The following is a modification to the above example which overrides the container memory and specifies an environment variable:

kind: BuildConfig
apiVersion: v1
metadata:
  name: openshift-jee-sample
spec:
  strategy:
    type: JenkinsPipeline
    jenkinsPipelineStrategy:
      jenkinsfile: |-
        podTemplate(label: "mypod", 1
                    cloud: "openshift", 2
                    inheritFrom: "maven", 3
                    containers: [
            containerTemplate(name: "jnlp", 4
                              image: "openshift/jenkins-slave-maven-centos7:v3.9", 5
                              resourceRequestMemory: "512Mi", 6
                              resourceLimitMemory: "512Mi", 7
                              envVars: [
              envVar(key: "CONTAINER_HEAP_PERCENT", value: "0.25") 8
            ])
          ]) {
          node("mypod") { 9
            sh "git clone https://github.com/openshift/openshift-jee-sample.git ."
            sh "mvn -B -Popenshift package"
            sh "oc start-build -F openshift-jee-sample-docker --from-file=target/ROOT.war"
          }
        }
  triggers:
  - type: ConfigChange

For more information on Kubernetes plug-in configuration, see the Kubernetes plug-in documentation.

When deployed by the provided Jenkins Ephemeral or Jenkins Persistent templates, the default memory limit is 512MiB.

See Sizing OpenJDK on OpenShift Container Platform for background information on tuning the JVM used by Jenkins.

For memory efficiency, by default the Jenkins image dynamically uses a 32-bit JVM if running in a container with a memory limit under 2GiB. This behavior can be overridden by the OPENSHIFT_JENKINS_JVM_ARCH environment variable.

By default the Jenkins JVM uses 50% of the container memory limit for its heap. This value can be modified by the CONTAINER_HEAP_PERCENT environment variable. It can also be capped at an upper limit or overridden entirely. See Environment Variables for more details.

Consider that by default all other processes executed in the Jenkins container, such as shell scripts or oc commands run locally from pipelines, are not likely to be able to use more than the remaining 256MiB memory combined without provoking an OOM kill. It is therefore highly recommended that pipelines run external commands in a slave container wherever possible.

It is recommended to specify memory request and limit values on slave containers created by the Jenkins Kubernetes Plug-in. As admin, defaults can be set on a per-slave image basis through the Jenkins configuration. The memory request and limit can also be overridden on a per-container basis as documented above.

You can increase the amount of memory available to Jenkins by overriding the MEMORY_LIMIT paramenter when instantiating the Jenkins Ephemeral or Jenkins Persistent template.

The OpenShift Container Platform Client Plug-in aims to provide a readable, concise, comprehensive, and fluent Jenkins Pipeline syntax for rich interactions with OpenShift Container Platform. The plug-in leverages the oc binary, which must be available on the nodes executing the script.

This plug-in is fully supported and is included in the Jenkins image. It provides:

See the OpenShift Pipeline Builds tutorial and the plug-in’s README for more information.

The OpenShift Container Platform Pipeline Plug-in is a prior integration between Jenkins and OpenShift Container Platform which provides less functionality than the OpenShift Container Platform Client Plug-in. It remains available and supported.

See the plug-in’s README for more information.

To facilitate OpenShift Container Platform Pipeline build strategy for integration between Jenkins and OpenShift Container Platform, the OpenShift Sync Plug-in monitors the API server of OpenShift Container Platform for updates to BuildConfigs and Builds that employ the Pipeline strategy and either creates Jenkins Pipeline projects (when a BuildConfig is created) or starts jobs in the resulting projects (when a Build is started).

As noted in Configuring the Jenkins Kubernetes Plug-in, this plug-in can create PodTemplate configurations for the Kubernetes plug-in based on specifically cited ImageStream, ImageStreamTag, or ConfigMap objects defined in OpenShift Container Platform.

This plug-in can now take Secret objects with a label key of credential.sync.jenkins.openshift.io and label value of true and construct Jenkins credentials which are placed in the default global domain within the Jenkins credentials hierarchy. The ID of the credential will be composed of the namespace the Secret is defined in, a hyphen (-), followed by the name of the Secret.

Similar to the handling of ConfigMaps for PodTemplates, the Secret object defined in OpenShift Container Platform is considered the master configuration. Any subsequent updates to the object in OpenShift Container Platform will be applied to the Jenkins credential (overwriting any changes to the credential made in the interim).

Removal of the credential.sync.jenkins.openshift.io property, setting of that property to something other than true, or deletion of the Secret in OpenShift Container Platform will result in deletion of the associated credential in Jenkins.

The type of secret will be mapped to the jenkins credential type as follows:

The Kubernetes plug-in is used to run Jenkins slaves as pods on your cluster. The auto-configuration of the Kubernetes plug-in is described in Using the Jenkins Kubernetes Plug-in.

Each Jenkins slave container can be configured with the following environment variables:

A JVM is used in all Jenkins slaves to host the Jenkins JNLP agent, as well as to run any Java applications (e.g. javac, Maven or Gradle). See Sizing OpenJDK on OpenShift Container Platform for background information on tuning the JVM used by Jenkins slaves.

For memory efficiency, by default the Jenkins image dynamically uses a 32-bit JVM if running in a container with a memory limit under 2GiB. This behavior can be overridden by the OPENSHIFT_JENKINS_JVM_ARCH environment variable. The JVM choice applies by default both for the Jenkins JNLP agent as well as for any other Java processes within the slave container.

By default the Jenkins JNLP agent JVM uses 50% of the container memory limit for its heap. This value can be modified by the CONTAINER_HEAP_PERCENT environment variable. It can also be capped at an upper limit or overridden entirely. See Environment Variables for more details.

Consider that by default any/all other processes executed in the Jenkins slave container, e.g. shell scripts or oc commands run from pipelines, may not be able to use more than the remaining 50% memory limit without provoking an OOM kill.

By default, each further JVM process run in a Jenkins slave container will use up to 25% of the container memory limit for their heap. It may be necessary to tune this for many build workloads. See Sizing OpenJDK on OpenShift Container Platform for more information.

See the Jenkins documentation for information on specifying the memory request and limit of a Jenkins slave container.