A Grub question

[John Morris]

On Thu, 2005-04-14 at 22:16, Chris Adams wrote:

> No, you install GRUB on real disk devices, not software RAID partitions.
> If /dev/md0 is your /boot and is on /dev/hda1 and /dev/hdb1 (and you
> want to install to the MBR), do:

Ok, while all of this Grub wizardry is assembled here, I have a
question.  Can you install grub in a partition instead of the MBR once
RAID gets involved?  I have tried several times and failed, having
trashed partitions and scrambled for rescue CDs many times in the
attempts.

Example:

Assume a pair of plain IDE drives as hda and hdb.  I have two different
installs on the drives so only one can claim the MBR, thus:

hda1/hdb1 = md0 / for the primary install
hda2/hdb2 = md1 swapspace
hda4/hdb4 = md2 /1 secondary install, reimages the primary, etc.

The preferred method, and what I used to use on workstations in my
primary location that aren't using RAID1, is to have the Grub in the MBR
kick off hda4 and the default option will chain boot hda1 which has a
version of grub which will boot hda1 and the normal environment.  If it
is horked up though, you simply hit the up arrow and pick "automated
recovery" and it boots hda4, which blows away hda1, reloads it and then
boots back into the main install.  Didn't work once I started using RAID
for the remote locations.  Now I have a sorty twitchy script on the
recovery partition that pulls in the right stanza for the primary
partition's kernel and stuffs it into it's copy of grub.conf.

I suspect this knowledge might also be useful for Windows victims since
it really wants to own the MBR for itself and has a nasty habit of
reclaiming it without advance notice.

-- 
John M.      http://www.beau.org/~jmorris     This post is 100% M$Free!
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