Date: Fri, 29 Mar 2024 12:15:41 +0000 From: Sad Clouds <cryintothebluesky@gmail.com> To: freebsd-questions@FreeBSD.org Subject: UFS snapshots and dump/restore Message-ID: <20240329121541.9b0163bef978b5e5fcfd54a7@gmail.com>
next in thread | raw e-mail | index | archive | help
Hello, I have questions about dump/restore which seem to ignore the
nodump flag for UFS snapshots:
Create snapshot:
# snapshot="/data/.snap/latest"
# mksnap_ffs ${snapshot} && chflags nodump ${snapshot}
Restore snapshot:
# snapshot="/data/.snap/latest"
# cd $(dirname ${snapshot})/../ &&
dump -0 -a -h 0 -C 16 -b 64 -f - ${snapshot} | restore -xuvf -
...
extract file ./.snap/latest
...
Despite the nodump flag, /data/.snap/latest is still dumped and
restored. This causes /data/.snap/latest to be reset to 0 bytes after
running restore and the snapshot is lost. Any idea why such behaviour?
What happens to the snapshot if I restore specific files, i.e.
# dump -0 -a -h 0 -C 16 -b 64 -f - ${snapshot} | restore -xuvf - ./file1 ./file2 ...etc
Can this cause inode numbers to change for those files in unpredictable
ways and cause corruption of the snapshot, or is this completely safe?
Thanks.
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20240329121541.9b0163bef978b5e5fcfd54a7>