So I was backing up ~250GB of data. Mounting the snapshot (to /tmp/mnt) and du -h /tmp/mnt/ shows, though, it’s ~1.3TiB in size.
Browsing through, some folders have the very same size as on the to-be-backed-up device, some others show a multiple of what they should be.
Weirdly, it’s just the directories. The files within appear correct.
Example:
root@backup-restore:~# du -sch /tmp/mnt/Aktiv/Reading /ORIG/Aktiv/Reading
3.4M /tmp/mnt/Aktiv/Reading
1.7M /ORIG/Aktiv/Reading
5.1M total
Checking the dir’s contents, though, it appears the same:
root@backup-restore:~# ls -la /tmp/mnt/Aktiv/Reading /ORIG/Aktiv/Reading
/ORIG/Aktiv/Reading:
total 1720
drwxrwxrwx 2 root root 4096 Jul 11 2024 .
drwxrwxrwx 14 root root 4096 Apr 19 2037 ..
-rw-rw-rw- 1 root root 1752161 Jul 11 2024 foobar.pdf
/tmp/mnt/Aktiv/Reading:
total 1712
-rw-rw-rw- 1 root root 1752161 Jul 11 2024 foobar.pdf
Quick search does not immediately reveal this as expected/documented behaviour.
OS is Debian/stable (bookworm) - inside an LXC container which is hypervised by Debian/trixie (testing)