On Fri, 12 Mar 2021 at 14:48, Victor Sudakov <vas@sibptus.ru> wrote: > David wrote: > > and then perhaps > > btrfs device remove ... > "Remove device(s) from a filesystem identified by <path>" > Hmm. /dev/nvme1n1 is not identified by any path because it's not mounted > as a btrfs filesystem. Yeah I expect you're supposed to 'btrfs remove' before replacing the filesystem with something different.