i'm not a master expert with linux raid, but... stop array, add 2 new disks and make a backup (dd) of two bad disks, start array with the new disks (must be same size) (i don't know if raid5 have spare disks and how they work, maybe there's a 'online' solution without stopping array) maybe others guys here could help you better, but this one works :) 2011/4/6 rob pfile <rpfile@xxxxxxxxx>: > Hi all, > > any collective wisdom on what to do here? i've got a 4-disk raid5, and the most recent checkarray showed several bad blocks caused by uncorrectable read errors on two of the disks in the array. both disks in question show 0 reallocated sectors, but one looks like this: > > 197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 0 > 198 Offline_Uncorrectable 0x0030 200 200 000 Old_age Offline - 16 > 199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0 > 200 Multi_Zone_Error_Rate 0x0008 200 200 000 Old_age Offline - 16 > > and the other like this: > > 197 Current_Pending_Sector 0x0032 200 200 000 Old_age Always - 14 > 198 Offline_Uncorrectable 0x0030 200 200 000 Old_age Offline - 3 > 199 UDMA_CRC_Error_Count 0x0032 200 200 000 Old_age Always - 0 > 200 Multi_Zone_Error_Rate 0x0008 200 200 000 Old_age Offline - 11 > > i'm a bit worried about failing one of these disks for fear that the other might give uncorrectable read errors during the rebuild. if i *had* to choose one, should i choose the one with all the pending sectors, or the one with all the uncorrectable sectors? > > does it makes sense to do a smartctl -t offline scan on one or both of these disks first? > > i guess i could take the array offline, clone one of the disks with dd, and then swap the clone in. but... is there a way to clone one disk in the array using mdadm? in other words, is there a way to construct a clean copy of one of the disks even if there are raid-correctable read errors? > > i do have backups, so perhaps it will not kill me if the array dies, but i'd like to tread carefully and try and get out of this mess without nuking everything. > > thanks for any advice, > > rob > > > > > > > > > > > > > > > -- > 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 > -- Roberto Spadim Spadim Technology / SPAEmpresarial -- 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
