> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > owner@xxxxxxxxxxxxxxx] On Behalf Of Philip Molter > Sent: Monday, September 01, 2008 1:32 PM > To: Linux RAID Mailing List > Subject: RAID1 disk failure causes hung mount > > Hello, > > We're running a modified version of the FC4 2.6.17 kernel (2.6.17.4). > I > realize this is an old kernel. For internal reasons, we cannot update > to a newer version of the kernel at this time. > > We have a 3ware 9550SXU card with 12 drives in JBOD mode. These 12 > drives are mirrored in 6 RAID1 pairs, then striped together in one big > RAID0 stripe. When we have a disk error with one of the drives in a > RAID1 pair, the entire RAID0 mount locks up. We can still cd to the > mount and read from it, but if we try to write anything to the mount, > the process hangs in an unkillable state. > > This recently happened. Here are the log messages from the disk > failure: > > sd 0:0:9:0: SCSI error: return code = 0x8000004 > sdj: Current: sense key: Medium Error > Additional sense: Unrecovered read error > end_request: I/O error, dev sdj, sector 10964975 > raid1: sdj1: rescheduling sector 10964912 > 3w-9xxx: scsi0: ERROR: (0x03:0x0202): Drive ECC error:port=9. > sd 0:0:9:0: SCSI error: return code = 0x8000004 > sdj: Current: sense key: Medium Error > Additional sense: Unrecovered read error > end_request: I/O error, dev sdj, sector 10964975 > raid1: sdd1: redirecting sector 10964912 to another mirror > > When this happened, /dev/sdj1 did not fail out of its RAID. It also > did > not lock the system. Later: > > sd 0:0:9:0: SCSI error: return code = 0x8000004 > sdj: Current: sense key: Medium Error > Additional sense: Unrecovered read error > end_request: I/O error, dev sdj, sector 16744439 > raid1: sdj1: rescheduling sector 16744376 > > When this happened, /dev/sdj1 did not fail out of its RAID, but it did > lock writes to the big RAID0 stripe. I manually failed /dev/sdj1 out > of > the RAID and /proc/mdstat did report it as failed out at that point. > It > did not cause writes to begin being processed. I tried to manually > remove /dev/sdj1 from the RAID and mdadm reported that the device was > busy. A hard power-cycle was required to restore functionality to the > system. This is consistent with these kinds of errors. > > I have looked through the patches related to RAID1 and lockups. The > patches from January/March 2008 related to RAID1 deadlocks have not > seemed to help (I didn't really expect them to as 2.6.17.4 predates > bitmap code, no?). > > I'd like to be able to get more debug during cases like this, but I'm > not sure what to gather or how to gather it. If anyone has any > suggestions, I'd appreciate hearing them. If any of the md devs have > any suggestions for patches to look at that specifically address this > behavior, I'd by very grateful for that advice. As it is, I've been > combing over git commits with very little success. > > Thanks in advance for any assistance, knowledge, or suggestions anyone > has. > > Philip Phillip: The problem really isn't with the LINUX kernel. Your 3WARE is the issue. Specifically, when the RAID1 "failed", LINUX did what it was supposed to do. /dev/sdj1 is the 3WARE-defined RAID1, and it generated a media error because it could not reconcile bad data on the RAID1 set. My guess is that you had a drive failure in combination with an unrecoverable read error on a physical block on the surviving disk in the pair. I write 3WARE-specific diags, and have code to drill down into the card and get debug info, and most likely repair the damage, but it is well beyond the scope of giving you a simple how-to, beyond booting 3WARE BIOS and doing data consistency checks on the broken RAID1. If you don't care about recovering data on the RAID0 slice, then do a consistency check/repair, and then you'll have only minor loss. If you want all of the data back, then you'll probably have to pay somebody for their time. Due to your hardware RAID component failure, it isn't really applicable to a software RAID forum. David ��.n��������+%������w��{.n�����{����w��ܨ}���Ơz�j:+v�����w����ޙ��&�)ߡ�a����z�ޗ���ݢj��w�f
