On Thu, 2008-08-21 at 21:15 -0700, mike wrote: > I've seen 5-6 disk zpools are the most recommended setup.
This is incorrect. Much larger zpools built out of striped redundant vdevs (mirror, raidz1, raidz2) are recommended and also work well. raidz1 or raidz2 vdevs of more than a single-digit number of drives are not recommended. so, for instance, the following is an appropriate use of 12 drives in two raidz2 sets of 6 disks, with 8 disks worth of raw space available: zpool create mypool raidz2 disk0 disk1 disk2 disk3 disk4 disk5 zpool add mypool raidz2 disk6 disk7 disk8 disk9 disk10 disk11 > In traditional RAID terms, I would like to do RAID5 + hot spare (13 > disks usable) out of the 15 disks (like raidz2 I suppose). What would > make the most sense to setup 15 disks with ~ 13 disks of usable space? Enable compression, and set up multiple raidz2 groups. Depending on what you're storing, you may get back more than you lose to parity. > This is for a home fileserver, I do not need HA/hotplugging/etc. so I > can tolerate a failure and replace it with plenty of time. It's not > mission critical. That's a lot of spindles for a home fileserver. I'd be inclined to go with a smaller number of larger disks in mirror pairs, allowing me to buy larger disks in pairs as they come on the market to increase capacity. > Same question, but 10 disks, and I'd sacrifice one for parity then. > Not two. so ~9 disks usable roughly (like raidz) zpool create mypool raidz1 disk0 disk1 disk2 disk3 disk4 zpool add mypool raidz1 disk5 disk6 disk7 disk8 disk9 8 disks raw capacity, can survive the loss of any one disk or the loss of two disks in different raidz groups. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
