Arch Linux

AnonMathematician

Member

Registered: 2019-10-12

Posts: 12

Cannot backup in timeshift with btrfs

I would like to use timeshift to create snapshots on my system. My disk is formatted btrfs and I would like to use the btrfs snapshot type as opposed to rsync. When I select my btrfs disk in timeshift it says "Select BTRFS system disk with root subvolume (@)." Here is my subvolume list and fstab:

 ➜  ~ sudo btrfs subvolume list /
ID 256 gen 25190 top level 5 path root
ID 259 gen 15 top level 256 path var/lib/portables
ID 260 gen 16 top level 256 path var/lib/machines
➜  ~ cat /etc/fstab 
# /dev/sda4
UUID=821595b5-1b44-4d92-9144-3c331cdcf19e	/         	btrfs     	rw,relatime,ssd,space_cache,subvolid=256,subvol=/root,subvol=root	0 0

# /dev/sda1
UUID=B683-67B4      	/boot     	vfat      	rw,relatime,fmask=0022,dmask=0022,codepage=437,iocharset=iso8859-1,shortname=mixed,utf8,errors=remount-ro	0 2

# /dev/sda3
UUID=931f6595-431b-4e0c-a791-21aa903b6ce6	none      	swap      	defaults  	0 0

It would appear my root subvolume is not indicated as "@." Is there a way to change this or is it something I should have configured during installation? Or are there other ways to fix this issue or other useful utilities I can use? I would prefer not to use rsync, but I likely will as a last resort.

I have referenced some other guides I have found online here and here without much luck. Any help would be appreciated. Thanks!

Ropid

Member

Registered: 2015-03-09

Posts: 1,069

Re: Cannot backup in timeshift with btrfs

You can rename a subvolume with the "mv" command, same as when renaming a normal directory or file.

I don't know how to work on this while the system is running. I think you need to do this work from the outside, while booting from the Arch ISO. Don't forget to edit the etc/fstab file, and the boot loader's config. You need to change the "subvol=/root" into "subvol=/@" there after you've renamed the subvolume.