accidentally replied offlist, so I'm trying to forward to the list for completeness
Right, the OpenBSD version at the time (15 years ago) I think was raidframe and they called it a serial number, it doesn't really matter as long as all the drives in the stack are the same. And it's mostly important if you've got multiple RAIDS and might mix the drives up. 10 years ago I might have whipped out my copy of Norton Disk Editor but that doesn't deal with LBA48, etc. dd and a hex editor could probably do it but unless you know exactly which bytes to change you're likely to damage something more important. So RTFM. One point of a RAID is that you can replace drives when they fail, so there's a way to put the serial number onto a new drive to match before you put it in. Just about any new drive will work as long as you can make a partition the same size as the rest of the drives. 5 or 10 years down the road it may be impractical to buy exactly the same size drive. So the makers of the RAID hardware/software will have provided a way to prepare a new replacement drive. You want to change it on all the drives at once, that's unusual. But there's nothing peculiar to Debian ARM about it. Try looking on http://superuser.com or posting a question there. Or maybe there's a RAID list or forum within Debian. Because of the larger userbase with i386/686 and AMD people you're more likely to find an answer. Or you could just live with it the way it is and tape a note onto each drive so you'll remember when you have to replace one. I've never used mdadm, I'm on an OpenBSD laptop which sometimes boots into Debian. My only running Debian right now is on my phone. No mdadm man page even. 15 years on OpenBSD, hmm. -- Credit is the root of all evil. - AB1JX
