OpenShift Container Platform

About adding volumes to a pod

You can add volumes and volume mounts to a pod. Volumes persist the data used by the containers, even if container crashes or stops.

You can add a volume, a volume mount, or both to pod templates by running the following command:

$ oc set volume <object_type>/<name> --add [options]

Table 4. Supported Options for Adding Volumes
Option	Description	Default
`--name`	Name of the volume.	Automatically generated, if not specified.
`-t, --type`	Name of the volume source. Supported values: `emptyDir`, `hostPath`, `secret`, `configmap`, `persistentVolumeClaim` or `projected`.	`emptyDir`
`-c, --containers`	Select containers by name. It can also take wildcard `'*'` that matches any character.	`'*'`
`-m, --mount-path`	Mount path inside the selected containers. Do not mount to the container root, `/`, or any path that is the same in the host and the container. This can corrupt your host system if the container is sufficiently privileged, such as the host `/dev/pts` files. It is safe to mount the host by using `/host`.
`--path`	Host path. Mandatory parameter for `--type=hostPath`. Do not mount to the container root, `/`, or any path that is the same in the host and the container. This can corrupt your host system if the container is sufficiently privileged, such as the host `/dev/pts` files. It is safe to mount the host by using `/host`.
`--secret-name`	Name of the secret. Mandatory parameter for `--type=secret`.
`--configmap-name`	Name of the configmap. Mandatory parameter for `--type=configmap`.
`--claim-name`	Name of the persistent volume claim. Mandatory parameter for `--type=persistentVolumeClaim`.
`--source`	Details of volume source as a JSON string. Recommended if the desired volume source is not supported by `--type`.
`-o, --output`	Display the modified objects instead of updating them on the server. Supported values: `json`, `yaml`.
`--output-version`	Output the modified objects with the given version.	`api-version`

For example:

To add a new volume source emptyDir to the registry DeploymentConfig object:

$ oc set volume dc/registry --add

You can alternatively apply the following YAML to add the volume:

Sample deployment config with an added volume

kind: DeploymentConfig
apiVersion: apps.openshift.io/v1
metadata:
  name: registry
  namespace: registry
spec:
  replicas: 3
  selector:
    app: httpd
  template:
    metadata:
      labels:
        app: httpd
    spec:
      volumes:
        - name: volume-pppsw
          emptyDir: {}
      containers:
        - name: httpd
          image: >-
            image-registry.openshift-image-registry.svc:5000/openshift/httpd:latest
          ports:
            - containerPort: 8080
              protocol: TCP

where:

spec.template.spec.volumes: Specifies the volume source emptyDir.

To add volume v1 with secret secret1 for replication controller r1 and mount inside the containers at /data:

$ oc set volume rc/r1 --add --name=v1 --type=secret --secret-name='secret1' --mount-path=/data

You can alternatively apply the following YAML to add the volume:

Sample replication controller with added volume and secret

kind: ReplicationController
apiVersion: v1
metadata:
  name: example-1
  namespace: example
spec:
  replicas: 0
  selector:
    app: httpd
    deployment: example-1
    deploymentconfig: example
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: httpd
        deployment: example-1
        deploymentconfig: example
    spec:
      volumes:
        - name: v1
          secret:
            secretName: secret1
            defaultMode: 420
      containers:
        - name: httpd
          image: >-
            image-registry.openshift-image-registry.svc:5000/openshift/httpd:latest
          volumeMounts:
            - name: v1
              mountPath: /data

where:

spec.template.spec.volumes: Specifies the volume and secret.
spec.template.spec.containers.volumeMounts: Specifies the container mount path.

To add existing persistent volume v1 with claim name pvc1 to deployment configuration dc.json on disk, mount the volume on container c1 at /data, and update the DeploymentConfig object on the server:

$ oc set volume -f dc.json --add --name=v1 --type=persistentVolumeClaim \
  --claim-name=pvc1 --mount-path=/data --containers=c1

You can alternatively apply the following YAML to add the volume:

Sample deployment config with persistent volume added

kind: DeploymentConfig
apiVersion: apps.openshift.io/v1
metadata:
  name: example
  namespace: example
spec:
  replicas: 3
  selector:
    app: httpd
  template:
    metadata:
      labels:
        app: httpd
    spec:
      volumes:
        - name: volume-pppsw
          emptyDir: {}
        - name: v1
          persistentVolumeClaim:
            claimName: pvc1
      containers:
        - name: httpd
          image: >-
            image-registry.openshift-image-registry.svc:5000/openshift/httpd:latest
          ports:
            - containerPort: 8080
              protocol: TCP
          volumeMounts:
            - name: v1
              mountPath: /data

where:

spec.template.spec.volumes.name.v1: Specifies the persistent volume claim named pvc1.
spec.template.spec.containers.volumeMounts: Specifies the container mount path.

To add a volume v1 based on Git repository https://github.com/namespace1/project1 with revision 5125c45f9f563 for all replication controllers:

$ oc set volume rc --all --add --name=v1 \
  --source='{"gitRepo": {
                "repository": "https://github.com/namespace1/project1",
                "revision": "5125c45f9f563"
            }}'