On Tue, November 16, 2010 22:56, Jim Dunham wrote: > Although ZFS is always on disk consistent, many applications are not > filesystem consistent. To be filesystem consistent, an application by > design must issue careful writes and/or synchronized filesystem > operations. Not knowing this fact, or lacking this functionality, a system > admin will need to deploy some of the work-arounds suggested above. The > most important one not listed, is to stop or pause those applications > which are know not to be filesystem consistent.
Windows has an API that ties into VSS/Shadow Copy where an application can register itself, and so when a back up app is running, it can tell everyone "please quiesce, we need to take a snapshot now". Applications can then create check points so that the snapshot will have consistent data, and that snapshot is what is backed up. It'd be useful for ZFS snapshots, but also for things like running in a virtualized environment (VMware, LDoms, etc.) where the hosting platform wants to create a checkpoint for the vDisks. Similarly for LUN snapshots under EMC, NetApp, etc. Currently such a mechanism / API does not exist in Solaris (or any Unix AFAICT): do you know if an RFE has been filed for such a thing? _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
