Hello Richard, Tuesday, October 17, 2006, 6:18:21 PM, you wrote:
REP> [editorial comment below :-)] REP> Matthew Ahrens wrote: >> Torrey McMahon wrote: >>> Richard Elling - PAE wrote: >>>> Anantha N. Srirama wrote: >>>>> I'm glad you asked this question. We are currently expecting 3511 >>>>> storage sub-systems for our servers. We were wondering about their >>>>> configuration as well. This ZFS thing throws a wrench in the old >>>>> line think ;-) Seriously, we now have to put on a new hat to figure >>>>> out the best way to leverage both the storage sub-system as well as >>>>> ZFS. >>>> >>>> [for the archives] >>>> There is *nothing wrong* with treating ZFS like UFS when configuring >>>> with LUNs >>>> hosted on RAID arrays. It is true that you will miss some of the >>>> self-healing >>>> features of ZFS, but at least you will know when the RAID array has >>>> munged your >>>> data -- a feature missing on UFS and most other file systems. >>> >>> Of you just offer ZFS multiple LUNs from the RAID array. >>> >>> The issue is putting ZFS on a single LUN be it a disk in a JBOD or a >>> LUN offered from a HW RAID array. If someone goes wrong and the LUN >>> becomes inaccessible then ... blamo! You're toasted. If ZFS detects a >>> data inconsistency then it can't look to an other block for a mirrored >>> copy, ala ZFS mirror, or to a parity block, ala RAIDZ. >> >> Right, I think Richard's point is that even if you just give ZFS a >> single LUN, ZFS is still more reliable than other filesystems (eg, due >> to its checksums to prevent silent data corruption and multiple copies >> of metadata to lessen the hurt of small amounts of data loss). When doing HW RAID and using ZFS as only the file system sometimes it could be worth to do striping in ZFS between LUNs (each LUN == RAID GROUP). That way file system metadata will be protected as each copy will be on different LUN (RAID group). REP> Richard pines for ditto data blocks :-) Well, I don't know - that way you end doing RAID in ZFS anyway so probably doing just RAID-10 in ZFS without ditto block would be better. -- Best regards, Robert mailto:[EMAIL PROTECTED] http://milek.blogspot.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
