On Sat, 2009-02-07 at 13:09 +1100, NeilBrown wrote: > On Sat, February 7, 2009 8:47 am, Thomas J. Baker wrote: > > On Sat, 2009-02-07 at 08:01 +1100, NeilBrown wrote: > >> On Sat, February 7, 2009 7:32 am, Thomas J. Baker wrote: > >> > >> > Thanks for the info. I think I follow everything. One last question > >> > before really trying it - is this what is expected when I actually run > >> > the command - the warnings about previous array, etc? > >> > >> Yes, you would expect exactly those messages. > >> > >> NeilBrown > >> > > > > OK, first I put the drives back to their original configuration (I had > > swapped two banks to make them appear physically as the kernel sees them > > logically to make it easier to track down the possibly faulty disks.) > > For clarity, I put them back to the original configuration before trying > > anything. > > > > Next I ran > > > > mdadm --create /dev/md0 --verbose --level=6 --raid-devices=26 \ > > /dev/sdb1 /dev/sdc1 /dev/sdd1 /dev/sde1 /dev/sdf1 /dev/sdg1 missing \ > > /dev/sdi1 missing /dev/sdk1 /dev/sdl1 /dev/sdm1 /dev/sdn1 /dev/sdo1 \ > > /dev/sdp1 /dev/sdq1 /dev/sdr1 /dev/sdt1 /dev/sdu1 /dev/sdv1 \ > > /dev/sdw1 /dev/sdx1 /dev/sdy1 /dev/sdz1 /dev/sdaa1 /dev/sdab1 > > > You said "--raid-devices=26". Why did you do that? > It should be '27'. > You need to have 25 real devices and 2 'missing' devices. > 24 of those real devices you can identify the correct position for > by looking at the --examine information from before you tried to > recreate the array. > The 25th real device you have to guess which is likely to be > the right one. > > > > > > which completed but when I fsck'd the disk, it wasn't happy, complaining > > about a missing superblock on /dev/md0. I then stopped the array. I'm > > not sure what to do next. It seems like the examine information of all > > the disks has been updated by the last create. I guess I should only go > > by the previous examine? As for the missing statement, should that only > > relate to drives with no md superblock? > > Yes, go by the previous examine information. > > The 'missing' can be any two devices. The important thing is the devices > that aren't 'missing'. They need to be devices that you have reason to > believe belong to that slot in the array. > > NeilBrown > OK, specifying 27 devices worked and I successfully mounted the RAID and looked around. Thanks again for the guidance! I guess things look OK (there are directories and files!) I was wondering if I should fsck it before adding the other two disks back in or after? Any other words of experience? Thanks again, tjb -- ======================================================================= | Thomas Baker email: tjb@xxxxxxx | | Systems Programmer | | Research Computing Center voice: (603) 862-4490 | | University of New Hampshire fax: (603) 862-1761 | | 332 Morse Hall | | Durham, NH 03824 USA http://wintermute.sr.unh.edu/~tjb | ======================================================================= -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
