On 2/16/2011 10:50 AM, Joel Sing wrote: > On Wednesday 16 February 2011, Steven R. Gerber wrote: >> Sorry for cross posting? >> I am trying to setup a decent RAID (0+1 or 1+0 or 5) and there SEEMS to >> be no approved method. (4 disks -- I usually like stripe on top of >> mirrors.) >> I believe that I have done my homework. >> What are my options? >> >> softraid (bioctl) cannot handle stripe on mirrors: >> I can easily create 2 mirrors and they survive reboot. >> I can create stripe on those mirrors (works -- can create files), but it >> does not survive reboot. > > Define "does not survive reboot". I'm guessing that you probably mean "fails > to automatically reassemble at boot", which is accurate - we do not currently > probe volumes that we have just assembled. Things should just work if you > manually assemble it after the mirrors are available. Note that this is not a > supported configuration, however it does seem to work - YMMV. > >> Message is device not configured. >> >> Both ccd and RAIDframe are decprecated (FAQ 14.13): >>> Software Options >>> OpenBSD supports softraid(4), a framework supporting many kinds of I/O >> >> transformations, including RAID and encryption disciplines. Softraid(4) >> is managed using bioctl(8). >> >>> OpenBSD also includes RAIDframe (raid(4), requires a custom kernel), >> >> and ccd(4) as historic ways of implementing RAID, but at this point >> OpenBSD does not suggest implementing either as a RAID solution for new >> installs or reinstalls. >> "OpenBSD does not suggest implementing either" >> Also, RAIDframe requires a custom kernel and we all know that GENERIC is >> preferred. >> >> RAID 5 is experimental (man bioctl): >>> CAVEATS >>> Use of the CRYPTO & RAID 4/5 disciplines are currently considered >>> experimental. >>> >>> OpenBSD 4.9 December 22, 2010 >> >> OpenBSD 4.9 >> >> Also, bioctl would not let me create a RAID 5 set: >> # bioctl -iv softraid0 >> # bioctl -c 5 -l /dev/sd1a,/dev/sd2a,/dev/sd3a,/dev/sd4a softraid0 >> bioctl: BIOCCREATERAID: Invalid argument >> # bioctl -iv softraid0 >> # dmesg|tail >> sd11 at scsibus6 targ 0 lun 0: <OPENBSD, SR RAID 0, 004> SCSI2 0/direct >> fixed >> sd11: 3815436MB, 512 bytes/sec, 7814014721 sec total >> sd11 detached >> scsibus6 detached >> sd10 detached >> scsibus5 detached >> sd9 detached >> scsibus4 detached >> softraid0: not part of the same volume >> softraid0: can't attach metadata type 0 > > You previously had a RAID 0 volume on some or all of these partitions, hence > the "not part of the same volume" and "can't attach metadata type 0" messages > (softraid is refusing to make members of a RAID 0 volume into a RAID 5 > volume). Either wipe the first 1MB or so of each partition (dd if=/dev/zero > of=/dev/rsd1a bs=1m count=1, etc) or use 'bioctl -C force ... '. > -- > > b Reason is not automatic. Those who deny it cannot be conquered by it. > Do not count on them. Leave them alone.b -- Ayn Rand > > >
"-C force" still fails (BUG!) I had to manually clear sd1...sd4 Now, I have an EXPERIMENTAL RAID 5 volume. Not the worst. *** sd9 at scsibus4 targ 0 lun 0: <OPENBSD, SR RAID 5, 004> SCSI2 0/direct fixed sd9: 5723178MB, 512 bytes/sec, 11721070081 sec total *** But, EXPERIMENTAL RAID 5 is dangerous (Marco Peereboom). OpenBSD softraid fully supports only RAID 0 (stripe) and RAID 1 (mirror). RAID 0 provides NO redundancy (not really RAID). RAID 1 is a waste beyond 2 disks. I want/need to use 4 (or more) disks. A real RAID (array) requires RAID 0+1 or RAID 1+0 or RAID 5 ... A custom kernel with RAIDframe is starting to look good. Still waiting for the next step ... Thanks, Steven
