[olug] The "other" raid utility usage

[Phil Brutsche]

A long time ago, in a galaxy far, far way, someone said...

> Hmm, interesting.  Hot swapping with a hardware RAID controller is old
> news, but I've never heard of doing it with software RAID on linux.  I'd
> be scared to pull a drive out of a running array for fear of what
> bizarre conniptions the SCSI driver would have.  Did you have to use a
> special utility to deactivate the drive first?

Yes, it possible.  You need to:

1) use raidhotremove to remove the drive from the array (important!)
2) use the sgutils Matt mentioned to stop the drive (and remove it from
Linux' knowledge)

before you remove it.  You reverse those steps to when you put the drive
(or the replacement, if it went bad) back in the system.

This will also work for any IDE RAID controller that works through the
SCSI bus, like the 3ware Escalade.

Note that you can't do this with pure IDE controllers, such as the Promise
- I hard locked 2.4.21-preX trying to do that (reset button wouldn't
recover the system properly, had to cold boot).

-- 

Phil Brutsche
phil at brutsche.us