Kyle McDonald wrote: > Chris Cosby wrote: >> About the best I can see: >> >> zpool create dirtypool raidz 250a 250b 320a raidz 320b 400a 400b raidz >> 500a 500b 750a >> >> And you have to do them in that order. The zpool will create using the >> smallest device. This gets you about 2140GB (500 + 640 + 1000) of >> space. Your desired method is only 2880GB (720 * 4) and is WAY harder >> to setup and maintain, especially if you get into the SDS configuration. >> >> I, for one, welcome our convoluted configuration overlords. I'd also >> like to see what the zpool looks like if it works. This is, obviously, >> untested. >> > I don't think I'd be that comfortable doing it, but I suppose you could > just add each drive as a separate vDev, and set copies=2, but even that > would get you about 1825GB (If my math is right the disks add up to 3650GB) > > -Kyle
There seems to be confusion about whether this works or not. - Marketing speak says metadata is redundant, and in case of at least two disks, it is distributed on at least two disks. - In case of filesystems where copies=2 this should also happen to file data - Which should mean that above configuration should be redundant and tolerate loss of one disk. - People having trouble on the list say that it does not work, if for any reason, after disk failure, the system shuts down, crashes, etc, because you cannot mount the pools - they are in unavailable state, even though according to marketing speak it should be possible to mount and go on, and recover all files with copies=2+, and for other files get information on which files are bad. - So, the QUESTION is: Is the marketing speak totally bogus, or is there missing code/bug/etc which prevents getting pool with a lost disk on-line (looping back to first question). Heikki >> chris >> >> >> On Fri, Aug 22, 2008 at 11:03 AM, Nils Goroll <[EMAIL PROTECTED] >> <mailto:[EMAIL PROTECTED]>> wrote: >> >> Hi, >> >> John wrote: >> > I'm setting up a ZFS fileserver using a bunch of spare drives. >> I'd like some redundancy and to maximize disk usage, so my plan >> was to use raid-z. The problem is that the drives are considerably >> mismatched and I haven't found documentation (though I don't see >> why it shouldn't be possible) to stripe smaller drives together to >> match bigger ones. The drives are: 1x750, 2x500, 2x400, 2x320, >> 2x250. Is it possible to accomplish the following with those drives: >> > >> > raid-z >> > 750 >> > 500+250=750 >> > 500+250=750 >> > 400+320=720 >> > 400+720=720 >> >> >> Though I've never used this in production, it seems possible to >> layer ZFS on good old SDS (aka SVM, disksuite). >> >> At least I managed to create a trivial pool on >> what-10-mins-ago-was-my-swap-slice: >> >> haggis:/var/tmp# metadb -f -a -c 3 /dev/dsk/c5t0d0s7 >> haggis:/var/tmp# metainit d10 1 1 /dev/dsk/c5t0d0s1 >> d10: Concat/Stripe is setup >> haggis:/var/tmp# zpool create test /dev/md/dsk/d10 >> haggis:/var/tmp# zpool status test >> pool: test >> state: ONLINE >> scrub: none requested >> config: >> >> NAME STATE READ WRITE CKSUM >> test ONLINE 0 0 0 >> /dev/md/dsk/d10 ONLINE 0 0 0 >> >> So it looks like you could do the follwing: >> >> * Put a small slice (10-20m should suffice, by convention it's >> slice 7 on the first cylinders) on each of your disks and make >> them the metadb, if you are not using SDS already >> metadb -f -a -c 3 <all your slices_7> >> >> make slice 0 the remainder of each disk >> >> * for your 500/250G drives, create a concat (stripe not possible) >> for each pair. for clarity, I'd recommend to include the 750G disk >> as well (syntax from memory, apologies if I'm wrong with details): >> >> metainit d11 1 1 <700G disk>s0 >> metainit d12 2 1 <500G disk>s0 1 <250G disk>s0 >> metainit d13 2 1 <500G disk>s0 1 <250G disk>s0 >> metainit d14 2 1 <400G disk>s0 1 <320G disk>s0 >> metainit d15 2 1 <400G disk>s0 1 <320G disk>s0 >> >> * create a raidz pool on your metadevices >> >> zpool create <name> raidz /dev/md/dsk/d11 /dev/md/dsk/d12 >> /dev/md/dsk/d13 /dev/md/dsk/d14 /dev/md/dsk/d15 >> >> Again: I have never tried this, so please don't blame me if this >> doesn't work. >> >> Nils >> >> >> This message posted from opensolaris.org <http://opensolaris.org> >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss@opensolaris.org <mailto:zfs-discuss@opensolaris.org> >> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >> >> >> >> >> -- >> chris -at- microcozm -dot- net >> === Si Hoc Legere Scis Nimium Eruditionis Habes >> ------------------------------------------------------------------------ >> >> _______________________________________________ >> zfs-discuss mailing list >> zfs-discuss@opensolaris.org >> http://mail.opensolaris.org/mailman/listinfo/zfs-discuss >> > > _______________________________________________ > zfs-discuss mailing list > zfs-discuss@opensolaris.org > http://mail.opensolaris.org/mailman/listinfo/zfs-discuss _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
