>> Do you want to keep the N-way mirror with N copies, but add a spare so
>> that when one of the N fails, it will start re-constructing immediately,
...
>> If the former, just `raidhotadd'.
> That is the one I was thinking of using.
Should be straightforward ...
> Will it automatically recognize it as a spare disk?
Yes.
> Do I need to worry about persistent-superblock
No.
> or is that a default with raidhotadd?
As I understand it, it adds it to the kernel tables.
If using PSB, these are flushed to the PSB.
> I can't find man pages for raidhotadd.
You didn't mention what version you are uing, and whence you got it ...
raidhotadd is just a link to raidstart ...
[ I don't have a man page either :-( ]
