[3043] in linux-scsi channel archive
Re: Dual-hosting SCSI and failure modes (was Re: RAID & unhappy scsi driver)
daemon@ATHENA.MIT.EDU (Gadi Oxman)
Tue Jan 6 03:28:44 1998
Date: Tue, 6 Jan 1998 10:20:56 +0300 (IST)
From: Gadi Oxman <gadio@netvision.net.il>
To: Andy Poling <andy@globalauctions.com>
cc: linas@linas.org, linux-raid@vger.rutgers.edu, linux-scsi@vger.rutgers.edu
In-Reply-To: <Pine.LNX.3.96.980105225109.16349F-100000@roadrunner.realbig.com>
On Mon, 5 Jan 1998, Andy Poling wrote:
> If you ask me, a bigger problem for recovery after a failed drive is the
> current device naming scheme that could potentially result in *all* of the
> remaining disks having different names after one is no longer available
> (presently hot swapped out, powered down or otherwise totally unresponsive).
The RAID-1/4/5 code is naming each RAID set with a unique random number,
and is further naming each drive in the set with a unique drive number.
As long as we "mdadd" all the drives to the set, the kernel code will
reconstruct the correct order by analyzing the RAID superblocks.
> Related item for the "it would make MD RAID truly awesome" wish list: scan
> all present disks for the MD RAID headers (trailers?) and automatically
> construct the correct device list to make up each MD device.
Should be relatively easy to implement, either in the kernel or in user-space.
Gadi
