According to Todd Whitesel:
>
>When I was using/adminning SunOS at my last job, tape drives and CD-ROMs
>were regularly moved around without rebooting machines:
>
>	umount (does this guarantee a sync?)
>	stop-A (suspend the kernel and enter debug firmware with ints masked)
>	unplug tape/cdrom and fix terminator
>	'go' (unsuspend the kernel)
>
>... and a similar reverse procedure for reconnecting things. I found that
>this worked quite well, and never once observed any fried hardware.
>

Ummmmm "don't try this at home kiddies" ;-)  I had a habit of doing
this as well.  I did not fry any hardware but I did fry a file system
beyond any hope of repair.  I had just taken some device off my
machine and did not put the terminator back on the chain properly
(very easy to do when you are sprawled over reaching for connectors
you cannot see).  When I did a go the kernel tried to update the disk
it got hard scsi errors and gave up on the update.  By the time I
managed to get the box back down and the scsi bus fixed my fs was
toast :-( 

-- 
Brett Lymn, Computer Systems Administrator, British Aerospace Australia
===============================================================================
  And the monks would cry unto them, "Keep the bloody noise down!"
  - Mort, Terry Pratchett.