I'm running Debian/Bookworm on an AMD64 system. I recently added a
second drive to it for use in a RAID1 array. However I'm now getting
regular messages about "SparesMissing event on...".
cat /proc/mdstat shows the problem: active raid1 sda1[0] sdb1[2] - the
newly added drive is showing up as [2] instead of [1]. Apparently mdadm
thinks there should be another drive sitting around as a spare.