I had perfectly working RAID5 and added another device. I lost power during the RAID recovery. Now I have no access to it - it does not exist - lsblk does no longer recognize it as RAID5 - just individual devices.
I have build a new RAID5 and trying to add one of the devices from the old array. I am getting "device busy" and the add is failing. I found a link solving this issue and started with this
$ sudo dmsetup table No devices found
Hence I stopped to follow the tutorial because it assumes some kind of "multipath" process and expects entries in the dmsetup table.
My questions are Is my process of build new array then add devices from the old reasonable ? How can I gain access to the old device or restore the old array?