Stateful application storage operations in Rancher

With Portworx, you can backup stateful applications and their volumes to an external object store and restore to the same cluster or to a new cluster. When it comes to timing, you can perform backup operations manually whenever you wish, or you can schedule them with a schedulePolicy. You can even use Portworx's backup functionality to clone applications between namespaces by restoring to a different namespace in the same cluster.

Prerequisites

All application storage operations require the following prerequisites:

• Administrator-level cluster privileges if you operate between namespaces

Configure Application Backups

Configure application backups by creating and applying the following CRDs:

• backupLocation
• applicationBackup

Create a backupLocation CRD

Use the backupLocation CRD to specify the configuration information for your object store. Portworx supports the following object stores:

• Any S3-compliant object store
• Azure Blob Storage
• Google Cloud Storage

The example in this document uses an S3 bucket to store application backup data. To create backupLocations using other object stores, see the Stateful application CRD reference section of the documentation.

"endpoint" : "bucketEndpoint.com"
"key": "ABCDEF1234567890"
"secret": "ABCDEF1234567890ABCDEF1234567890ABCDEF1234567890"

If you're restoring backups to a different cluster from the one you took your backups from, you must create a backupLocation CRD on your new cluster that matches the backupLocation CRD on your original cluster.

note

If you want to use S3 Object Lock, refer to S3 Object Lock in PX-Backup.

You can specify your object store credentials directly in the BackupLocation configuration as plaintext or use a Kubernetes secret:

Plaintext credentials

1. Create backLo.yaml file, specifying the following:

• name: the backupLocation object's name
• namespace: the namespace the backupLocation exists in
• location:

  • type: the object store type

  • path: the bucket Portworx will use for the backup

  • sync: If you're restoring to a new cluster, set sync to true to allow your new cluster to retrieve the previous backups from your backup location.

  • s3Config:

    • region: which region your s3 bucket is located in

    • accessKeyID: your bucket's accessKeyID

    • secretAccessKey: your bucket's secretAccessKey

    • endpoint: the URL or IP address of your bucket

    • disableSSL: whether or not to disable SSL

      apiVersion: stork.libopenstorage.org/v1alpha1
      kind: BackupLocation
      metadata:
        name: mysql
        namespace: mysql-app
        annotations:
          stork.libopenstorage.org/skipresource: "true"
      location:
        type: s3
        path: "bucket-name"
        sync: true
        s3Config:
          region: us-east-1
          accessKeyID: XXXX
          secretAccessKey: XXXX
          endpoint: "https://bucketEndpoint.com"
          disableSSL: false

    note

    If you use URL as your bucket endpoint, you must include the http prefix: either https:// or http://, depending on whether or not you're using SSL.

2. Apply the YAML:

   kubectl apply -f backLo.yaml

Kubernetes secret containing your credentials

1. Create a Kubernetes Secret YAML file named s3secret.yaml, specifying the following:

• name: the Secret object's name
• namespace: the namespace the Secret exists in

• stringData:

  • region: which region your s3 bucket is located in

  • accessKeyID: your bucket's accessKeyID

  • secretAccessKey: your bucket's secretAccessKey

  • endpoint: the URL or IP address of your bucket

  • disableSSL: whether or not to disable SSL

  • encryptionKey: your secret's encryption key

      apiVersion: v1
      kind: Secret
      metadata:
        name: s3secret
        namespace: mysql
        annotations:
          stork.libopenstorage.org/skipresource: "true"
      stringData:
        region: us-east-1
        accessKeyID: <access-key>
        secretAccessKey: <secret-key>
        endpoint: "X.X.X.141:9010"
        disableSSL: "false"
        encryptionKey: "testKey"

2. Apply the Secret's YAML file:

   kubectl apply -f s3secret.yaml

3. Create a backupLocation YAML file, specifying the following:

• name: the backupLocation object's name
• namespace: the namespace the backupLocation exists in
• location:

  • type: the object store type

  • path: the bucket Portworx will use for the backup

  • secretConfig: the Secret object containing your bucket's credentials

  • sync: If you're restoring to a new cluster, set sync to true to allow your new cluster to retrieve the previous backups from your backup location.

    apiVersion: stork.libopenstorage.org/v1alpha1
    kind: BackupLocation
    metadata:
      name: mysql-backup
      namespace: mysql
      annotations:
        stork.libopenstorage.org/skipresource: "true"
    location:
      type: s3
      path: "bucket-name"
      secretConfig: s3secret
      sync: true

note

If you use URL as your bucket endpoint, you must include the http prefix: either https:// or http://, depending on whether or not you're using SSL.

4. Apply the YAML:

   kubectl apply -f backLo.yaml

Create an applicationBackup CRD

Use the applicationBackup CRD to specify what namespaces have their applications backed-up.

1. Create an applicationbackup YAML file named appBack.yaml, specifying the following:

• name: the applicationBackup object's name

• namespace: the namespace the applicationBackup exists in

• spec:

  • backupLocation: what backupLocation object to use to determine where to send the backup
  • namespaces: the namespaces to backup
  • reclaimPolicy: what happens to objects in the object store when the ApplicationBackup object is deleted, either Delete or Retain
  • selectors: define specific labels to determine which objects and volumes are backed-up
  • preExecRule: what rule to run before performing backup
  • postExecRule: what rule to run after performing backup

  apiVersion: stork.libopenstorage.org/v1alpha1
  kind: ApplicationBackup
  metadata:
    name: backup
    namespace: mysql-app
  spec:
    backupLocation: mysql
    namespaces:
    - mysql-app
    reclaimPolicy: Delete
    selectors:
    preExecRule:
    postExecRule:

2. Apply the YAML:

   kubectl apply -f appBack.yaml

3. Verify the applicationBackup object's status with the storkctl get command. You can see what stage the backup is in, as well as its status:

   storkctl get applicationbackup -n mysql-app

   NAME      STAGE     STATUS    VOLUMES   RESOURCES   CREATED               ELAPSED
   backup    Volumes   Pending   0/0       0           11 Sep 19 22:10 UTC   19.023065649s

   You can also describe the object to get more information about the backup. This is useful for troubleshooting:

   kubectl describe applicationbackup.stork.libopenstorage.org -n mysql-app

   The following error message displays when your credentials are invalid.

   Warning  Failed  7s  stork  Error starting ApplicationBackup for volumes: rpc error: code = Internal desc = Failed to create backup: Failed to validate credentials: error validating credential: AccessDenied: Access Denied.
            status code: 403, request id: 15C38376E0A0EA7F, host id:

Create an ApplicationBackupSchedule CRD

The ApplicationBackupSchedule CRD associates a SchedulePolicy with an application backup operation, allowing you to schedule when and how application backups are performed.

1. Create a file named backupSchedulePolicy.yaml with the following content:

   apiVersion: stork.libopenstorage.org/v1alpha1
   kind: SchedulePolicy
   metadata:
     name: backupSchedule
   policy:
     interval:
       intervalMinutes: 60
       retain: 5
     daily:
       time: "10:14PM"
       retain: 5
     weekly:
       day: "Thursday"
       time: "10:13PM"
       retain: 5
     monthly:
       date: 14
       time: "8:05PM"
       retain: 5

   For details about how you can configure a schedule policy, see the SchedulePolicy page.

2. Apply the spec by entering the following command:

   kubectl apply -f backupSchedulePolicy.yaml

3. Display your schedule policy. Enter the storkctl get command passing it the name of your policy:

   storkctl get schedulepolicy

   NAME           INTERVAL-MINUTES   DAILY     WEEKLY             MONTHLY
   testpolicy     60                 10:14PM   Thursday@10:13PM   14@8:05PM

4. Create a file named applicationbackupSchedule.yaml, specifying the following:

• name: the applicationBackupSchedule object's name

• namespace: the namespace the applicationBackupSchedule exists in

• spec.schedulePolicyName: the name of the schedule policy that defines when backup actions happen

• spec.template.spec.backupLocation: the name of the backup location spec

• spec.template.spec.namespaces: namespaces which will be backed up

• spec.template.spec.reclaimPolicy: what happens to objects in the object store when the ApplicationBackup object is deleted

  apiVersion: stork.libopenstorage.org/v1alpha1
  kind: ApplicationBackupSchedule
  metadata:
    name: backup
    namespace: mysql
  spec:
    schedulePolicyName: testpolicy
    template:
      spec:
        backupLocation: mysql
        namespaces:
        - mysql
        reclaimPolicy: Delete

5. Apply the spec by entering the following command:

   kubectl apply -f applicationbackupSchedule.yaml

Restore an application

You can restore an application by applying an ApplicationRestore object.

1. Create an ApplicationRestore YAML file named appRestore.yaml, specifying the following:

• name: the ApplicationRestore object's name
• namespace: the ApplicationRestore object's namespace
• spec.backupName: the name of the applicationBackup object to restore from
• spec.backupLocation: which backup location object to get application backups from
• spec.namespaceMapping: a map of source and destination namespaces, allowing you to restore a backup to a different namespace
• spec.replacePolicy: specifies whether you want to delete or retain any matching existing resource in the target namespace

apiVersion: stork.libopenstorage.org/v1alpha1
kind: ApplicationRestore
metadata:
  name: restore
  namespace: mysql-app
spec:
  backupName: backup
  backupLocation: mysql
  namespaceMapping:
    <backup_namespace>: <restore_namespace>
  replacePolicy: Delete

note

You can run the storkctl get applicationbackup -n namespace command to help you see which backup to restore from.

2. Apply the YAML:

kubectl apply -f appRestore.yaml

The moment you apply the YAML, the application begins to restore. Monitor the status with the storkctl get command:

storkctl get applicationrestore -n mysql-app

NAME      STAGE     STATUS       VOLUMES   RESOURCES   CREATED               ELAPSED
restore   Final     Successful   1/1       3           11 Sep 19 23:32 UTC   35s

Verify its status with the kubectl get pods command:

kubectl get pods -n mysql-app

NAME                     READY   STATUS    RESTARTS   AGE
mysql-6d69b99774-2bv4m   0/1     Pending   0          3s

note

To restore an application to a different cluster, here are the additional steps that you need to perform:

• On the destination cluster, create BackupLocation CRD.

• From the source cluster, get completed ApplicationBackup CR YAML and save it in a file with command:

  kubectl get ApplicationBackup <Backup-Which-need-to-be-Restored> -oyaml > backup-completed.yaml

• Apply the above YAML to the destination cluster:

  kubectl apply -f backup-completed.yaml

Clone an Application

You can clone an application to a different namespace. You must create the ApplicationClone object in the admin namespace, which is kube-system by default.

note

• Distributed apps, such as Cassandra, may use the same node IDs on the destination namespace as their source, causing disruption when the new nodes join the source cluster.

1. Create an ApplicationClone YAML file named appClone.yaml, specifying the following:

   • name: the ApplicationClone object's name

   • namespace: the ApplicationClone object's namespace

   • spec.sourceNamespace: the namespace you want to clone applications from

   • spec.destinationNamespace: the namespace you want to clone applications to

     apiVersion: stork.libopenstorage.org/v1alpha1
     kind: ApplicationClone
     metadata:
       name: clone-mysql
       namespace: kube-system
     spec:
       sourceNamespace: mysql-app
       destinationNamespace: clone-mysql

2. Apply the YAML file:

   kubectl apply -f appClone.yaml