>On Apr 13, 2010, at 5:22 AM, Tony MacDoodle wrote: > >> I was wondering if any data was lost while doing a snapshot on a >running system? > >ZFS will not lose data during a snapshot. > >> Does it flush everything to disk or would some stuff be lost? > >Yes, all ZFS data will be committed to disk and then the snapshot >is taken. >
Hi Richard. Can you explain in a little bit more detail how this process works? Let's say you are writing from a remote virtual machine via an iscsi target set for async writes and I take a snapshot of that volume. Are you saying any outstanding writes for that volume will need to be written to disk before the snapshot happens? Setting the target to sync writes and using a ZIL might have better performance, if you were doing a lot of snapshots. I know there is a potential to lose data with async set target, but the virtual machines running on the system are just lab machines using non-production data. BTW, great Nexenta / ZFS class in Atlanta. Thanks for getting me on the right track!! Geoff _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
