On Fri, 20 Jul 2012 17:10:14 +0800 "vincent" <hanguozhong@xxxxxxxxxxxx> wrote: > Hi, everyone: > I am Vincent, I am writing to you to ask a question about of > mdadm. > I created a raid10 array with 4 160G disks used the command: mdadm > -Cv /dev/md0 -l10 -n4 /dev/sd[abcd], > The version of my mdadm is 3.2.2, and the version of my kernel is > 2.6.38 > when the raid10 is in resyncing, I used the following command to > make file system for it: mkfs.ext3 /dev/md0 > every was OK. The array continued to resync, but when the process > of resyncing is 3.4%, there were a lot of > IO error of "sda" and "sdc". There were bad blocks in sda and sdc. > Then I used "cat /proc/mdstat" to see the status of /dev/md0: > > Personalities : [raid10] > md0 : active raid10 sdb[1] sdd[3] > 310343680 blocks super 1.2 512K chunks 2 near-copies [4/2] [_U_U] > > unused devices: <none> > > /dev/sdc and /dev/sda had lost. > Then I reboot the system, but when i used "cat /proc/mdstat" to > see the status of /dev/md0: > > Personalities : [raid10] > md126 : active raid10 sda[0] sdc[2] > 310343680 blocks super 1.2 512K chunks 2 near-copies [4/2] [U_U_] > > md0 : active raid10 sdb[1] sdd[3] > 310343680 blocks super 1.2 512K chunks 2 near-copies [4/2] [_U_U] > > unused devices: <none> > > there had a array which name was md126, and consisted by /dev/sdc > /dev/sda. > I used "mdadm --assemble --scan" to assemble the md devices. the > output of the command is: > > dm: /dev/md/0 exists - ignoring > md: md0 stopped. > mdadm: ignoring /dev/sda as it reports /dev/sdd as failed > mdadm: ignoring /dev/sdc as it reports /dev/sdd as failed > md: bind<sdd> > md: bind<sdb> > md/raid10:md0: active with 2 out of 4 devices > md0: detected capacity change from 0 to 317791928320 > mdadm: /dev/md0 has been started with 2 drives (out of 4). > md0: unknown partition table > mdadm: /dev/md/0 exists - ignoring > md: md126 stopped. > md: bind<sdc> > md: bind<sda> > md/raid10:md126: active with 2 out of 4 devices > md126: detected capacity change from 0 to 317791928320 > mdadm: /dev/md126 has been started with 2 drives (out of 4). > md126: unknown partition table > > And then I used "mdadm -E /dev/sda", "mdadm -E /dev/sdb", "mdadm > -E /dev/sdc", "mdadm -E /dev/sdc" , > "mdadm -D /dev/md0" and "mdadm -D /dev/md127" to check the > details info of sda, sdb, sdc and sdd. > I found the property of "Array UUID" of all of these devices(sda, > sdb, sdc, sdd)were the same. But the > property of "Events" and "Update Time" of "sda" and "sdc" were the > same(21, Fri Jul 6 11:02:09 2012), > the property of "Events" and "Update Time" of "sdb" and "sdd" were > the same(35, Fri Jul 6 11:06:21 2012). > > Although the "Update Time" and "events" property of "sda" and > "sdc" were not equal to "sdb" and "sdd", > they had the same "Array UUID". why this array tend to two > degraded arrays those had the same uuid? > As the two arrays had the same uuid, it is difficult to > distinguish and use them. I think it is unreasonable, > could you help me ? > Yes, this is a known problem. Hopefully it will be fixed in the next release of mdadm. For now, just remove the faulty devices, or at least remove the metadata from them with mdadm --zero-superblock /dev/sd[ac] NeilBrown
Attachment:
signature.asc
Description: PGP signature
