2850 drive bays not hot-swap?

[Brett Dikeman]

I have a 2850 with the RAID card disabled- using the drives directly,
in two RAID sets.

Testing the mirror RAID set for the system drive, I pulled a drive,
made sure everything still worked, then plugged it back in and tried
to add it back to the software array, which failed.  I received the
following kernel messages trying to use fdisk just to see if I could
do anything with the drive:

"Buffer I/O error on device sdb, logical block 1"
(then repeated for logical block 2, 3, 0, 35843684, 35843684 again,
then 0, 1, and 2 again.  Looking for the partition table, I presume.)

After a reboot, the drive was added back in and rebuilt successfully.

The documentation for the machine says the bays are hot-swap U320.  Is
there something special needed on the Linux side or with the mpt
controller driver to get this hot-swap goodness?  Or are they only
hot-swap when using the RAID functions of the controller?

This system is running Debian Lenny's kernel (2.6.22-3-amd64) and has
the latest BIOS/firmware for all components, as of a month or two ago.

Brett