Hey there,
I’m in need of a bit of wisdom here:
I recently got myself a shiny new Vserver and have it running exclusively with docker containers that use regular volumes.
Now: how would I back this thing up? I mean, I have read a lot about borg for example, but I’m not sure how to do it the right way:
Do I just copy / to a repo and fiddle the data back in place if stuff goes wrong, or would it be wiser to backup the volumes, do a docker save and export the images to a folder and then send that to the storage box?
Since docker should stop the containers to prevent data inconsistency during a backup: How do I tell Borg to do that? I’ve seen several approaches (Borg Dockerized with some sort of access to docker’s .sock, Borg setup on the host, and some even wilder approaches).
Since Backups aren’t something you can “try again” once you need them, I’d rather have a solution that works.
For my personal stuff, I use docker compose to create bind mounts for all volumes (including databases). These are all within a docker-compose directory. Then I use a cron job to shut down the containers, then zip up the docker-compose directories and start the containers again.
It’s important to shut them down so anything in RAM is written to disk.
The way to make sure your backups are working is to regularly restore from them (generally into a VM for me).
Just here to echo this. Hope is not a plan.
Taking a backup is a warm fuzzy. Restoring is a nail biter.
I wanted to migrate to a bigger SSD. I did it by backing up my old one with rsnapshot then restoring onto a fresh Linux install on the new SSD. I had to update /etc/fstab to mount my new SSD instead of my old one, and that was it! Easy peasy. Now I have backups and restores tested, too. And then I just set up a cron job to keep backing everything up nightly.