On 06.04.2021 22:05, Devon Beets wrote: > Output of the recommended commands for adding the new disk to the RAID5 array: > > sudo mdadm -R --force /dev/md126 > mdadm: array /dev/md/Data now has 3 devices (0 new) > > sudo mdadm -S /dev/md125 > mdadm: stopped /dev/md125 > > sudo mdadm -a /dev/md127 /dev/sdb > mdadm: added /dev/sdb > > Output of mdstat after running the commands. Shows that both md126 and md127 are inactive, and there is no RAID resync happening. > > cat /proc/mdstat > Personalities : [raid6] [raid5] [raid4] [linear] [multipath] [raid0] [raid1] [raid10] > md126 : inactive sda[2] sdc[1] sdd[0] > 5567507712 blocks super external:/md127/0 > > md127 : inactive sdb[3](S) sdc[2](S) sdd[1](S) sda[0](S) > 10564 blocks super external:imsm > > unused devices: <none> It looks like mdadm still does not handle this case correctly. Please do this before the "mdadm -R --force /dev/md126": printf "%llu\n" -1 > /sys/block/md126/md/resync_start Regards, Artur
