On Tue, 2006-06-27 at 17:50, Erik Trimble wrote: > Since the best way to get this is to use a Mirror or RAIDZ vdev, I'm > assuming that the proper way to get benefits from both ZFS and HW RAID > is the following: > > (1) ZFS mirror of HW stripes, i.e. "zpool create tank mirror > hwStripe1 hwStripe2" > (2) ZFS RAIDZ of HW mirrors, i.e. "zpool create tank raidz hwMirror1, > hwMirror2" > (3) ZFS RAIDZ of HW stripes, i.e. "zpool create tank raidz hwStripe1, > hwStripe2" > > mirrors of mirrors and raidz of raid5 is also possible, but I'm pretty > sure they're considerably less useful than the 3 above. > > Personally, I can't think of a good reason to use ZFS with HW RAID5; > case (3) above seems to me to provide better performance with roughly > the same amount of redundancy (not quite true, but close).
You really need some level of redundancy if you're using HW raid. Using plain stripes is downright dangerous. 0+1 vs 1+0 and all that. Seems to me that the simplest way to go is to use zfs to mirror HW raid5, preferably with the HW raid5 LUNs being completely independent disks attached to completely independent controllers with no components or datapaths in common. -- -Peter Tribble L.I.S., University of Hertfordshire - http://www.herts.ac.uk/ http://www.petertribble.co.uk/ - http://ptribble.blogspot.com/ _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
