I am storing my containers on an ext4 file system and as @woosting has pointed out, lxc-snapshot is unable to create ‘true’ snapshots on ext4 because it’s not supported by the file system.
That said, I was able to create a copy-clone successfully. (If the filesystem doesn’t support snapshots, it reverts to copy cloning instead).
root@turris:~# echo "Fully working Guacamole with 2FA, Let's Encrypt SSL using NGINX" > snap-comm && lxc-snapshot -n guac-srv -c snap-comm && rm snap-comm
lxc-snapshot: lxccontainer.c: do_lxcapi_snapshot: 3209 Snapshot of directory-backed container requested.
lxc-snapshot: lxccontainer.c: do_lxcapi_snapshot: 3210 Making a copy-clone. If you do want snapshots, then
lxc-snapshot: lxccontainer.c: do_lxcapi_snapshot: 3211 please create an aufs or overlayfs clone first, snapshot that
lxc-snapshot: lxccontainer.c: do_lxcapi_snapshot: 3212 and keep the original container pristine.
For my current setup, lxc-snapshot is working as intended seeing as I’m using an FS that doesn’t support snapshots anyway.
Is anyone here using a non-ext4 file system that would be willing to try running lxc-snapshot to see if they’re able to get true snapshots working (i.e. not just copy-clone)?