I installed Kubuntu 26.04 using the default ext4 filesystem, but I'm considering switching the system drive to Btrfs for features such as snapshots and built-in deduplication. I've found tools like btrfs-convert, but I'm concerned about data loss and whether they're safe for a drive that contains the operating system. Is conversion practical, or should I back everything up and reinstall?
4 Answers
The safest and most supported approach is to make a verified backup, reformat the target filesystem as Btrfs, reinstall the system, and restore your files. In-place conversion may be possible with btrfs-convert, but it adds complexity and potential failure points, especially on a boot installation. Don’t attempt it without a tested backup.
If your personal files are on a separate /home partition, you can back up that partition, reinstall the operating system using Btrfs, and restore or reuse /home. Still make a separate backup first, because reinstalling and changing partitions can go wrong. If /home is part of the same filesystem, you’ll need to copy it elsewhere before reformatting.
btrfs-convert is a real tool included with btrfs-progs, and experienced users have used it successfully. However, it usually requires working from a live environment or chroot and troubleshooting the boot setup afterward. A clean reinstall is generally less risky and easier to recover if something goes wrong.
Btrfs snapshots don’t become useful automatically just because the filesystem is Btrfs. You normally need an appropriate subvolume layout plus snapshot, bootloader, and rollback integration. Setting that up after installation can be awkward, so a distribution or installer that configures snapshots from the beginning may be a better choice. Also, snapshots are not backups, and Btrfs deduplication is not generally automatic without additional tools.
That makes sense. I’d rather avoid an elaborate recovery process just to gain features I may not actually need.