How to create Application-Aware Backups

It’s possible to define annotations on Pods with backup commands. These backup commands should create an application-aware backup and stream it to stdout.

Define an annotation on a Pod:

<SNIP>
template:
  metadata:
    labels:
      app: mariadb
    annotations:
      k8up.syn.tools/backupcommand: mysqldump -uroot -psecure --all-databases
<SNIP>yaml

With this annotation the Operator will trigger that command inside the the container and capture the stdout to a backup. The command is only executed on one Pod, if there are multiple Pods with the same owner reference (e.g. Deployments, Statefulsets etc).

Tested with:

MariaDB
MongoDB
tar to stdout

But it should work with any command that has the ability to output the backup to stdout.