A huge thank you to all who gave advice!! The issue was the BBL I decided to just run with a --update=force-no-bbl for a few reasons * I was sure those bad blocks were read errors generated a long time ago due to a faulty SATA cable * Since then I have noted a couple of corrupt files but nothing of importance and I just generally delete anything corrupt anyway * Anything irreplaceable on the raid was backed up elsewhere * I did not trust myself with finding + fixing the bad blocks manually, and felt it might just get me into more trouble * Almost anything that touched the raid while active was hanging the terminal (even a fdisk -l) making trying things painful So cowboy style I just ran mdadm --assemble --update=force-no-bbl -v /dev/md0 /dev/sd[fgdecb]1 And Boom! it started doing its thing without a hiccup. About 12h on a reshape, then 6hr on a resync, after that I did a "fsck.ext4 -f /dev/md0" with no issues found, so a "resize2fs /dev/md0" and finally a mount. I have since tested a heap of data and hasn't missed a beat. mdadm --examine isn't reporting bad blocks anymore, not sure if they are silently waiting to cause me problems in the future but appears ok for now. Thanks again for all the help and advice! Nice to see my array healthy again :) $ mdadm --detail /dev/md0 /dev/md0: Version : 1.2 Creation Time : Sun Dec 2 12:04:24 2012 Raid Level : raid5 Array Size : 14651317760 (13972.59 GiB 15002.95 GB) Used Dev Size : 2930263552 (2794.52 GiB 3000.59 GB) Raid Devices : 6 Total Devices : 6 Persistence : Superblock is persistent Update Time : Thu Dec 7 19:26:53 2017 State : clean Active Devices : 6 Working Devices : 6 Failed Devices : 0 Spare Devices : 0 Layout : left-symmetric Chunk Size : 512K Name : homer2:1 UUID : f39f89d2:1bcd3d55:d173d206:d85b8bbc Events : 4835083 Number Major Minor RaidDevice State 8 8 81 0 active sync /dev/sdf1 6 8 97 1 active sync /dev/sdg1 5 8 49 2 active sync /dev/sdd1 9 8 65 3 active sync /dev/sde1 7 8 33 4 active sync /dev/sdc1 10 8 17 5 active sync /dev/sdb1 $ cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] [linear] [multipath] [raid0] [raid1] [raid10] md0 : active raid5 sdd1[5] sdc1[7] sdb1[10] sde1[9] sdg1[6] sdf1[8] 14651317760 blocks super 1.2 level 5, 512k chunk, algorithm 2 [6/6] [UUUUUU] unused devices: <none> end<div id="DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2"><br /> <table style="border-top: 1px solid #D3D4DE;"> <tr> <td style="width: 55px; padding-top: 13px;"><a href="http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail" target="_blank"><img src="https://ipmcdn.avast.com/images/icons/icon-envelope-tick-green-avg-v1.png" alt="" width="46" height="29" style="width: 46px; height: 29px;" /></a></td> <td style="width: 470px; padding-top: 12px; color: #41424e; font-size: 13px; font-family: Arial, Helvetica, sans-serif; line-height: 18px;">Virus-free. <a href="http://www.avg.com/email-signature?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail" target="_blank" style="color: #4453ea;">www.avg.com</a> </td> </tr> </table><a href="#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2" width="1" height="1"></a></div> -- 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