Chapter 2. Backing up and restoring projects and applications

You can manually back up and restore data for your projects and applications.

Important

Backup and restore is not guaranteed. You are responsible for backing up your own data.

2.1. Backing up application data

In many cases, you can back up application data by using the oc rsync command, assuming rsync is installed within the container image. The Red Hat rhel7 base image contains rsync. Therefore, all images that are based on rhel7 contain it as well. See Troubleshooting and Debugging CLI Operations - rsync.

Warning

This is a generic backup of application data and does not take into account application-specific backup procedures, for example, special export and import procedures for database systems.

Other means of backup might exist depending on the type of the persistent volume you use, for example, Cinder, NFS, or Gluster.

The paths to back up are also application specific. You can determine what path to back up by looking at the mountPath for volumes in the deploymentconfig.

Note

You can perform this type of application data backup only while the application pod is running.

Procedure

Example of backing up a Jenkins deployment’s application data

  1. Get the application data mountPath from the deploymentconfig: 

    $ oc get dc/jenkins -o jsonpath='{ .spec.template.spec.containers[?(@.name=="jenkins")].volumeMounts[?(@.name=="jenkins-data")].mountPath }'
/var/lib/jenkins

  2. Get the name of the pod that is currently running: 

    $ oc get pod --selector=deploymentconfig=jenkins -o jsonpath='{ .metadata.name }'
jenkins-1-37nux

  3. Use the oc rsync command to copy application data: 

    $ oc rsync jenkins-1-37nux:/var/lib/jenkins /tmp/

2.2. Backing up a project

Creating a backup of all relevant data involves exporting all important information, then restoring into a new project.

Note

Currently, a OpenShift Dedicated project back up and restore tool is being developed by Red Hat. See the following bug for more information:

Procedure

  1. List all the relevant data to back up: 

    $ oc get all
NAME         TYPE      FROM      LATEST
bc/ruby-ex   Source    Git       1

NAME               TYPE      FROM          STATUS     STARTED         DURATION
builds/ruby-ex-1   Source    Git@c457001   Complete   2 minutes ago   35s

NAME                 DOCKER REPO                                     TAGS      UPDATED
is/guestbook         10.111.255.221:5000/myproject/guestbook         latest    2 minutes ago
is/hello-openshift   10.111.255.221:5000/myproject/hello-openshift   latest    2 minutes ago
is/ruby-22-centos7   10.111.255.221:5000/myproject/ruby-22-centos7   latest    2 minutes ago
is/ruby-ex           10.111.255.221:5000/myproject/ruby-ex           latest    2 minutes ago

NAME                 REVISION   DESIRED   CURRENT   TRIGGERED BY
dc/guestbook         1          1         1         config,image(guestbook:latest)
dc/hello-openshift   1          1         1         config,image(hello-openshift:latest)
dc/ruby-ex           1          1         1         config,image(ruby-ex:latest)

NAME                   DESIRED   CURRENT   READY     AGE
rc/guestbook-1         1         1         1         2m
rc/hello-openshift-1   1         1         1         2m
rc/ruby-ex-1           1         1         1         2m

NAME                  CLUSTER-IP       EXTERNAL-IP   PORT(S)             AGE
svc/guestbook         10.111.105.84    <none>        3000/TCP            2m
svc/hello-openshift   10.111.230.24    <none>        8080/TCP,8888/TCP   2m
svc/ruby-ex           10.111.232.117   <none>        8080/TCP            2m

NAME                         READY     STATUS      RESTARTS   AGE
po/guestbook-1-c010g         1/1       Running     0          2m
po/hello-openshift-1-4zw2q   1/1       Running     0          2m
po/ruby-ex-1-build           0/1       Completed   0          2m
po/ruby-ex-1-rxc74           1/1       Running     0          2m

  2. Export the project objects to a .yaml or .json file.

    • To export the project objects into a project.yaml file: 

      $ oc export all -o yaml > project.yaml

    • To export the project objects into a project.json file: 

      $ oc export all -o json > project.json

  3. Export the project’s role bindings, secrets, service accounts, and persistent volume claims: 

    $ for object in rolebindings serviceaccounts secrets imagestreamtags podpreset cms egressnetworkpolicies rolebindingrestrictions limitranges resourcequotas pvcs templates cronjobs statefulsets hpas deployments replicasets poddisruptionbudget endpoints
do
  oc export $object -o yaml > $object.yaml
done

  4. To list all the namespaced objects: 

    $ oc api-resources --namespaced=true -o name

  5. Some exported objects can rely on specific metadata or references to unique IDs in the project. This is a limitation on the usability of the recreated objects.

    When using imagestreams, the image parameter of a deploymentconfig can point to a specific sha checksum of an image in the internal registry that would not exist in a restored environment. For instance, running the sample "ruby-ex" as oc new-app centos/ruby-22-centos7~https://github.com/sclorg/ruby-ex.git creates an imagestream ruby-ex using the internal registry to host the image: 

    $ oc get dc ruby-ex -o jsonpath="{.spec.template.spec.containers[].image}"
10.111.255.221:5000/myproject/ruby-ex@sha256:880c720b23c8d15a53b01db52f7abdcbb2280e03f686a5c8edfef1a2a7b21cee

    If importing the deploymentconfig as it is exported with oc export it fails if the image does not exist.

2.3. Restoring application data

You can restore application data by using the oc rsync command, assuming rsync is installed within the container image. The Red Hat rhel7 base image contains rsync. Therefore, all images that are based on rhel7 contain it as well. See Troubleshooting and Debugging CLI Operations - rsync.

Warning

This is a generic restoration of application data and does not take into account application-specific backup procedures, for example, special export and import procedures for database systems.

Other means of restoration might exist depending on the type of the persistent volume you use, for example, Cinder, NFS, or Gluster.

Procedure

Example of restoring a Jenkins deployment’s application data

  1. Verify the backup: 

    $ ls -la /tmp/jenkins-backup/
total 8
drwxrwxr-x.  3 user     user   20 Sep  6 11:14 .
drwxrwxrwt. 17 root     root 4096 Sep  6 11:16 ..
drwxrwsrwx. 12 user     user 4096 Sep  6 11:14 jenkins

  2. Use the oc rsync tool to copy the data into the running pod: 

    $ oc rsync /tmp/jenkins-backup/jenkins jenkins-1-37nux:/var/lib
    Note

    Depending on the application, you may be required to restart the application.

  3. Optionally, restart the application with new data: 

    $ oc delete pod jenkins-1-37nux

    Alternatively, you can scale down the deployment to 0, and then up again: 

    $ oc scale --replicas=0 dc/jenkins
$ oc scale --replicas=1 dc/jenkins

2.3.1. Restoring a project

To restore a project, create the new project, then restore any exported files by running oc create -f pods.json. However, restoring a project from scratch requires a specific order because some objects depend on others. For example, you must create the configmaps before you create any pods.

Procedure

  1. If the project was exported as a single file, import it by running the following commands: 

    $ oc new-project <projectname>
$ oc create -f project.yaml
$ oc create -f secret.yaml
$ oc create -f serviceaccount.yaml
$ oc create -f pvc.yaml
$ oc create -f rolebindings.yaml
    Warning

    Some resources, such as pods and default service accounts, can fail to be created.