Longhorn supports recurring snapshot and backup for volumes. User only need to set when he/she wish to take the snapshot and/or backup, and how many snapshots/backups needs to be retains, then Longhorn will automatically create snapshot/backup for the user at that time, as long as the volume is attached to a node.

Users can setup recurring snapshot/backup via Longhorn UI, or Kubernetes StorageClass.

Set up recurring jobs using Longhorn UI

User can find the setting for the recurring snapshot and backup in the Volume Detail page.

Set up recurring jobs using StorageClass

Users can set field recurringJobs in StorageClass as parameters. Any future volumes created using this StorageClass will have those recurring jobs automatically set up.

Field recurringJobs should follow JSON format. e.g.

  1. kind: StorageClass
  2. apiVersion: storage.k8s.io/v1
  3. metadata:
  4.   name: longhorn
  5. provisioner: driver.longhorn.io
  6. parameters:
  7.   numberOfReplicas: "3"
  8.   staleReplicaTimeout: "30"
  9.   fromBackup: ""
  10.   recurringJobs: '[{"name":"snap", "task":"snapshot", "cron":"*/1 * * * *", "retain":1},
  11.                    {"name":"backup", "task":"backup", "cron":"*/2 * * * *", "retain":1}]'

Explanation:

  1. name: Name of one job. Do not use duplicate name in one recurringJobs. And the length of name should be no more than 8 characters.

  2. task: Type of one job. It supports snapshot (periodically create snapshot) or backup (periodically create snapshot then do backup) only.

  3. cron: Cron expression. It tells execution time of one job.

  4. retain: How many snapshots/backups Longhorn will retain for one job. It should be no less than 1.