replacing a hot-swap disk

[Steven Bellovin <smb%cs.columbia.edu@localhost>]

I need to replace a failing disk on a server.  The hardware is hot- 
swap SATA; can NetBSD handle removing and replacing it without a  
reboot?  I'd quiesce the device (by failing it with 'raidctl -f')  
first.  The replacement disk is not the same model, but has the same  
number of sectors.

                --Steve Bellovin, http://www.cs.columbia.edu/~smb