On 2026-01-08 02:38, William Park via Talk wrote:
Now, to move it to storage.
(1) Within the same BTRFS system. Well, you just did it. Or, you can "mv" to different location. Treat it like "read-only" directory.
(2) To another BTRFS system. (This is my case). You have to "dump" over stdin/stdout,
btrfs send home--2026-01-06 | btrfs receive /backup/
A new read-only snapshot will show up at /backup/home--2026-01-06. With my SATA2 harddisks, I get about 60MB/s throughput.
Nowadays, you can buy a single big harddisk. But, if you want to re- purpose old harddisks, then BTRFS is the only reasonable filesystem that can pull multiple harddisks together.
(3) To copy to EXT4 system. Since subvolume is directory,
cp -a home--2026-01-06 /backup/ or tar -cf - home--2026-01-06 | tar -xf - -C /backup/ or find ... | cpio ...
Update: I tried "incremental" backup, and it's FAST. You can try it out locally. - Create 2 snapshots of /home, say /home.1, /home.2. btrtr subvolume snapshot -r /home /home.1 btrtr subvolume snapshot -r /home /home.2 - Copy the first one normally. time btrfs send /home.1 | btrfs receive /backup - Copy the second one incrementally, using the first as base. time btrfs send -p /home.1 /home.2 | btrfs receive /backup The only drawback is, you have to keep same set of backups on both side, sender and receiver. But, because they're snapshots, they don't take much room. That completes my migration journey. --William