Recreating the default btrfs setup on a migrated btrfs partition


I have converted my root partition from ext4 to btrfs ( I have /home setup on xfs ).

I know that there is a list of subvolumes created by default, but of course my converted partition has none. And snapper is not set up either.

To create the subvolumes I am considering using a live USB stick and creating the subvolumes after booting from it in rescue mode:

Once all is complete, reboot and validate that all the files are in the right places.

After that I would create the root config for snapper and delete the data which now lives in subvolumes.

Is there anything missing from these steps that the default BTRFS setup is doing? Are these steps ( at least in theory ) correct?



To be clear, this being Tumbleweed, is it fully up to date and working normally right now on the converted root partition?

What size is your root partition (if default it may be 20GB)? On Tw, mine is 35GB and with a reduced snapper config it’s never exceeded 30GB used. With a drastically reduced config e.g completely disabling hourly timeline snapshots, it has not exceeded 20GB and averages around 15GB of used space. [/QUOTE]

It seems you have done your research carefully. :wink:

It’s been a long time since I added a subvolume for the inclusive /home back on 12.3 just prior to upgrading it to old Tumbleweed. If I remember correctly I did that using Yast > System > Partitioner on the live system. Following the edit, it conveniently takes care of subvolume creation, mount, and fstab.

The improved partitioner looks even better now. Select your Btrfs partition in the left pane, and use “Edit…” button in the right pane. You then see “Mounting Options” and “Subvolume Handling” feature buttons etc. My default subvolumes listed there includes:


…and the rest are entries for each retained snapshot on root partition e.g. .snapshots/1234/snapshots

The list is important, as you probably know, the subvolumes are always excluded from actual snapshots.

Clearly, the partitioner can also be used from your live media.

Thanks for confirming the general direction, I created the subvolumes based on a default Tumbleweed install and then copied the data over. Everything worked like a charm.

Note that my TW Live USB stick did not have yast2 available when started in rescue mode but I did not spend too much time on it.


Always good to hear news like that. :slight_smile:

Note that my TW Live USB stick did not have yast2 available when started in rescue mode but I did not spend too much time on it.

Duly noted, thanks for mentioning.