alt Hacker NewsHow do I backup docker volumes? I never found a native flow for backing up docker compose projects.
While not built in k8s has at least velero and kasten. However they are only possible because of snapshots https://kubernetes.io/docs/concepts/storage/volume-snapshots... and kasten has a plugin like architecture (because of k8s ) that supports application specific backups. However I never found something like that for compose. And that is troublesome in bigger projects like sentry
Replies
The "easiest" way is to use bind mounts to a local directory (or multiple directories) instead of volumes. Then you can just use normal backup tooling.
Docker volumes (and bind mounts) however have the minor problem of being hard to get a consistent copy to without stopping the service. You can work around this by, e. G., having ZFS or btrfs as the underlying FS and making a snapshot there. Otherwise, your software (like PostgreSQL) might also have other online backup tooling.
Why use a docker volume? Seems like a good way to accidentally lose your files. Just volume-mount from the external filesystem and back it up the same way you would any linux application's files - maybe stop it, maybe not, depends on how it uses files.