Since raidadd/raidrun have been replaced with raidstart
and raidstart lacks some of the functionality of starting
raid devices, the user must use "persistent-superblock 1"
for each raid device, or when the raid is stopped,
raidstart will not start it.

All the /etc/raidtab is fine, but without this option in
each raiddev stanze, if you raidstop the device, the
next time I try to raidstart it, I messages in
/var/log/messages of the type:

	kernel: (read) sdc1's sb offset: 8883840 [events: ea5fe76b]
	kernel: md: invalid raid superblock magic on sdc1
	kernel: md: sdc1 has invalid sb, not importing!
	kernel: could not import sdc1!
	kernel: autostart sdc1 failed!
	kernel: huh12?

Simply adding the persistant-superblock removes this
problem.  Without it, the first time you reboot, you lose
your raid.

It would be nice if this were documented as a "must do",
and if it were mentioned in all the sample raidtabs in
/usr/doc/raidtools-0.90, not just raid0.conf.sample in
that direcotory.