On Mon, 2009-03-16 at 21:51 +0530, dushyanth.h@xxxxxxxxxxx wrote: > Hi guys, > > Iam using dm-multipath for a Infortrend dual controller F16F-R4031-6 FC > system. > > Version details are : > > device-mapper-multipath-0.4.7-17.el5 > device-mapper-1.02.24-1.el5 > device-mapper-event-1.02.24-1.el5 > > OS : Red Hat Enterprise Linux Server release 5.2 (Tikanga) > Kernel : 2.6.18-92.1.10.el5 #1 SMP x86_64 x86_64 x86_64 > > Recently, one of the RAID controllers failed and caused multipath to > fail both active paths > > device-mapper: multipath: Failing path 8:32. 8:32 has failed here. > sd 2:0:0:0: SCSI error: return code = 0x00020000 error code 20000 mean the BUS is busy. > end_request: I/O error, dev sdd, sector 1976776672 > device-mapper: multipath: Failing path 8:48. and 8:48 failed because of that. Do you know which one was supposed to fail when the RAID controller failed ? (my guess is it is 8:32). looks like for whatever reason the other SCSI bus became busy. > sd 2:0:0:0: SCSI error: return code = 0x00020000 > end_request: I/O error, dev sdd, sector 1967432880 > sd 2:0:0:0: SCSI error: return code = 0x00020000 > end_request: I/O error, dev sdd, sector 161647296 > > This caused the ext3 filesystem to go into a read only mode. Full IO > errors is at http://pastebin.com/m103325d9 > > The dual controller storage unit and the host server (Only 1 Server > using 2 Qlogic FC HBAs) are hooked upto two different Qlogic SanBox FC > switch for redundancy. > > multipath.conf : http://pastebin.com/m4c7da817 > multipath -v4 -ll : http://pastebin.com/m7d863925 > > I have checked the logs on the FC switch and the HBAs > and i dont see any event which suggest both paths failed at once. Even > the errors i captured out of dmesg show that one of the physical disks > that makes up dm-0 had 'end_request: I/O errors' while the other did not > have any such error. > > sd 2:0:0:0: SCSI error: return code = 0x00020000 > end_request: I/O error, dev sdd, sector 1967432880 > sd 2:0:0:0: SCSI error: return code = 0x00020000 > end_request: I/O error, dev sdd, sector 161647296 > > At this point iam wondering how paths 8:32 and 8:48 failed together - > considering both paths are through two different FC switches. Any > suggestions on this ? > > Additionaly, I have looked at the mailing list archives & annotated conf > files and found two options a) failback and b) no_path_retry. What would > be the best recommended values for these on a dual controller setup like > mine ? > > It would also be helpful if someone could share infotrend specific > settings multipath settings. > > TIA > Dushyanth > > > -- > dm-devel mailing list > dm-devel@xxxxxxxxxx > https://www.redhat.com/mailman/listinfo/dm-devel -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
