Subject: Re: Upgrading OS for an environment using Raid
To: David Laight <david@l8s.co.uk>
From: Greg Oster <oster@cs.usask.ca>
List: current-users
Date: 01/04/2004 18:46:35
David Laight writes:
> > For the special case of RAID1 sets and install media, adding the
> > ability to find and read this label might be quite
> > beneficial. Thoughts?
> 
> This is similar to the problem of installing the system in the first place.
> Someone wrote some long, error prone, instructions and posted a URL....
> 
> It ought to be possible to (on i386 at least) to initially install
> with a 64 sector gap [1] before the netbsd partition, then fiddle the
> disk layout so that became the raid header (hand waves all the raid
> commands).

Yes.

> Upgrading could be done by breaking the mirror and then making the
> original install area bootable again.
> (With a few tweaks the raid set and raw disk could be selected by the
> mbr-bootsel code - but you probably wouldn't want to make that easy!
> 
> 	David
> 
> [1] Greg might be persuaded to make the 64 a parameter of the raid header,
> a track multiple might be a better value - and needed on some systems.

You mean like:

#define RF_PROTECTED_SECTORS 64L    /* # of sectors at start of disk to
                                       exclude from RAID address space */

in /usr/include/dev/raidframe/raidframevar.h ?  :)  (Sorry.. it's not 
been as advertised as well as it might have been...)

Later...

Greg Oster