Backup and Recovery
The backup plugin was deprecated in 0.4.x, below are backup recommendations for 0.5.x and later.
Backup and Migration Tutorial
Because Dokku is git based, rebuilding a deployed app is as easy as pushing from git. You can push to a new server by updating the dokku remote in you local app's repo.
Some plugins, like the official dokku-postgres plugin, have built-in commands that allow non-volatile data be exported and imported.
For dokku-postgres, use:
Volumes and Static Assets
Dokku doesn't enforce a 300mb limit on apps, but it's best practice to keep binary assets outside of git. Since containers are considered volatile in Dokku, external stores like s3 or storage mounts should be used for non-volatile items like user uploads. The dokku storage core plugin can be used to mount local directories / volumes inside the docker container.
The best plan for disaster recovery is to always keep multiple (remote) copies of your local repo, static assets and periodic database dumps. In case of an emergency when your git repo and backups are completely lost, you can recover the last pushed copy from your remote dokku server (assuming you still have the ssh key).