Snapshots should be able to be generated on an active filesystem in full
flight. If you cannot do that then something is wrong.
I have had many issues with LVM snapshots and XFS/xfs_freeze but that was a
long time ago (last year and early this year) you might check the archives to
see if the issue is something simular. For me I stopped using xfs_freeze and
relied on the VFS-lock patch.
I did have a problem that was time related. If I ran through snapshots
manually everything worked. If I ran exactly the same commands in a script
it would die. I don't think anyone was able to work it out. In the end I
changed that way I was doing it.
> I think I know what I was doing wrong. I had the script I was
> writing/executing on the filesystem I was trying to snapshot.
> Bad idea!!!!
> I have moved my script to a drive I don't need to snapshot, and it seems to
> be running reliably now.
> Before I figured this out, I locked up LVM so bad a couple of times that I
> had to cycle power on the server. :<
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