On 06/30/2016 11:33 AM, Grunewald, Soeren wrote: > Hi All, > > After a crash, probably caused by some raid issue, the array can't be > assembled again. It looks like 8 disk were disappearing form the raid at > the same time, which then lead to the system crash. Now I'm unable to > get the array back to live again. Because the whole system was on the > failing array, I can't access any additional information to check what > happened. The system is a 8 year old SUN Fire X4540 system running under > Ubuntu 12.04.5 (kernel-3.13.0-91 and mdadm-3.2.5-1ubuntu0.3), which is > mainly used for data conversion (converting very large files from one > format into another). The boot partition is placed on a 2GB ssd and the > rest is running on the 48disk raid6 array. I have booted the system from > a usb stick with clonezilla (kernel 4.4.x + mdadm 3.3) and started > digging... > > Since this is the first time, that a I face such a large array and such > an issue, I better follow the advice from the Linux-Raid-Wiki and > request for help. > > As one can see in the attached log, the 'Events' count of 40 drives is > 4391 and 4385 for the 8 others. We have the same picture for the > 'State', 40 drives state 'clean' and 8 drives 'active'. So I tried > 'mdadm --assemble --force ...'. This fixed the event count and faulty > flag on 4 of the 8 disks. But still the array can't be created. > > Except one smart error (1 Currently unreadable (pending) sectors) do all > other drives pass the extended smart test. I know, this does not mean > that the drives are not damaged or broken. > > Anyway, how should I process to get the array working again? > You're the second person in the last month to run into this... There was a bug in mdadm that makes it fail with --assemble --force when there are several out-of-date devices. The fix was to clone the mdadm git tree, compile the latest, and run that stand-alone binary to perform the forced assembly. I haven't tried to determine which released version has the fix. Phil -- 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
