[linux-lvm] Snapshot weirdness
khudson at tsss.org
Thu Nov 3 23:53:03 UTC 2005
I'm building a disk-to-disk-to-tape backup appliance here, and decided
that for maximum flexibility I'd use LVM2 (mainly because of its
snapshot feature and the ability to hot-add disks and extend volumes
seamlessly. Good stuff.)
Anyhow, I have a 600GB primary physical volume configured with a single
logical volume utilizing 99% of the extents. I have the system set to
take a snapshot every night so there's always a live copy of the data
available for backup. Three such snapshots are used in rotation (the
oldest snapshot is deleted and recreated as the newest); each occupy 25
extents. The problem is, after some time, I'll have a bunch of errors
regarding the snapshot volumes spewed to the system logs and console. If
I subsequently try and read from the filesystem, the kernel shuts the
filesystem down (XFS feature).
This makes it rather inconvenient to back up a snapshot -- if I can't
read it, it doesn't do me much good to have it. I'm basically using the
snapshots read-only, and the filesystems are mounted as such, as well.
So, can anyone shed some insight on why I have self-corrupting
filesystems on my snapshot volumes?
Thanks in advance.
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