> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > owner@xxxxxxxxxxxxxxx] On Behalf Of Pierre Vignéras > Sent: Sunday, May 16, 2010 10:41 AM > To: linux-raid@xxxxxxxxxxxxxxx > Subject: mdadm: failed devices become spares! > > Hi, > > I encountered a critical problem with mdadm that I submitted to the Debian > mailing list (it's a debian lenny/stable). They asked me to submit this to > you. So that's what I do. > > To prevent duplication of description/information, I give you the URL of > that > bug description: > > http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=578352 > > If you prefer the full stuff to be copy/pasted to that mailing list, just > ask > for it. > > Note: that bug happened again today, on another RAID array. So the good > news > is that it is somewhat reproducible! The bad news, is that unless you have > a > magic solution, all my data are just lost (half of it was in the backup > pipe!)... > > Thanks for any help, and regards. > -- > Pierre Vignéras It's not quite clear to me from the link whether your drives are truly toast, or not. If they are, then you are hosed. Assuming not, then you need to use `mdadm --examine /dev/sdxx` and `mdadm -Dt /dev/mdyy` to determine precisely all the parameters and the order of the block devices in the array. You need the chunk size, the superblock type, which slot was occupied by each device in the array (this may not be the same as when the array was created), the size of the array (if it did not fill the entire partition in every case), the RAID level, etc. Once you are certain you have all the information to enable you to re-create the array, if need be, the try to re-assemble the array with `mdadm --assemble --force /dev/mdyy` If it works, then fsck the file system. (I think I noticed you are using XFS. If so, do not use XFS_Check. Instead, use XFS_Repair with the -n option.) After you have a clean file system, issue the command `echo repair > /sys/block/mdyy/md/sync_action` to re-sync the array. If the array does not assemble, then you will need to stop it and re-create it using the options you obtained from your research above and adding the --assume-clean switch to prevent a resync if something is wrong. If the fsck won't work after re-creating the array, then you probably got one or more of the parameters incorrect. -- 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
