On Sun, Jun 23, 2013 at 06:24:39PM -0500, Eric Sandeen wrote: > On 6/23/13 5:55 PM, Dave Chinner wrote: > > On Fri, Jun 21, 2013 at 10:30:31PM -0700, aurfalien wrote: > >> Hi all, > >> > >> So I have an XFS file system within LVM which has an external log. > >> > >> My mount option in FSTAB is; > >> > >> /dev/vg_spock_data/lv_data /data xfs logdev=/dev/sdc1,nobarrier,logbufs=8,noatime,nodiratime 1 1 > >> > >> All is well no issues and very fast. > >> > >> Now I'd like to snapshot this bad boy and then run rsnapshot to create a few days backup. > > > > You need to snapshot the log device as well. > > > > But that is problematic in that you need to snapshot it at the same > > time you snapshot the data volume. Hence yo'd have to do: > > > > # xfs_freeze -f <filesystem> > > # <snapshot data volume> > > # <snapshot log volume> > > # xfs_freeze -u <filesystem> > > > > And now you can mount the snapshot with: > > > > # mount /dev/vg_spock_data/datasnapshot /snapshot -o nouuid,ro,logdev=/dev/vg_spock_log/logsnapshot > > > > If you can't snapshot the log device, then you can't snapshot the > > filesystem. Yet another reason for using internal logs... > > Hm, given that freezing the fs makes the log (almost) completely clean, I wonder > if he could mount with /dev/zero (or a loopback 0-filled file) to get at the snapshot, > especially since it's being mounted RO. > > Should be safe & consistent, no? In theory. Never tried it myself. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
