So, I moved my nextcloud directory from a local SATA drive to a NFS mount from a nvme array on a 10G network

“I just need to change /docker/nextcloud to /mnt/nfs/nextcloud in the docker-compose.yml, what’s the issue, i do it live” - i tell myself

So i stop the container, copy /docker/nextcloud to /mnt/nfs/nextcloud, then edit the docker-compose.yml… and… because I’m doing it during a phone call without paying too much attention i change the main directory to /docker

I rebuild the container and I immediately hear a flood of telegram notifications from my uptime-kuma bot… oh oh…

Looks like the nextcloud docker image has an initialization script that if it doesn’t find the files in the directory, it will delete everything and install a fresh copy of nextcloud… so it deleted everything on my server

Luckily i had a very recent full borg backup and i’m restoring it (i kinda love-hate borg, i always forget the restore commands when in panic and the docs are a bit cryptic for me)

Lessons learned:

  1. always double check everything

  2. offsite backups are a must (if i accidentally wrote / as path, i would have lost also the borg backups!)

  3. offsite backups should not be permanently mounted, otherwise they would have been wiped as well

  4. learn how to use and schedule filesystem snapshots, so the recovery wouldn’t take ages like it’s taking right now (2+ hours and i’m not even half way…)

      • 4am@lemm.eeEnglish
        2·
        1 year ago

        Be aware that, in the past anyway, Docker didn’t like some storage mediums when running in LXC (I think there are [were?] issues if you snapshot the LXC image on ZFS and you’re using the Overlay2 driver for Docker), and that you could often find issues with networking that way as well (might be a problem if you are trying to cluster/swarm between multiple LXCs?). For those reasons I’ve kept all my Docker stuff in kvm rather than LXC, I wasn’t experienced enough to untangle it all.