[clue] revisiting boot partition and LVM + grub

mike havlicek mhavlicek1 at yahoo.com
Mon Mar 12 16:01:07 MDT 2012



 

________________________________
 From: David L. Anselmi <anselmi at anselmi.us>
To: mike havlicek <mhavlicek1 at yahoo.com>; CLUE's mailing list <clue at cluedenver.org> 
Sent: Monday, March 12, 2012 11:52 AM
Subject: Re: [clue] revisiting boot partition and LVM + grub
 
===============================================================================================
> This leads me to a question of defeating my purpose (separate /boot disk area within lvm so as to
> be able to resize when an update involving the kernel is possibly going to go over available
> space and I am not yet sure what backup kernel(s) I am ready to remove)

I've never had a good reason to use a separate boot partition.  Others have told me 2:

Using the same (probably custom built) kernel with several distros.  So all distros share the same /boot.  If you're using stock kernel packages that seems error prone and with initramfs I'm not sure how possible it is these days.  Regardless, I've never wanted to do it.

Putting root on a partition that can't be booted from (e.g., using grub with LVM).  I used LILO to boot off LVM until grub2 could handle it.  Today I don't have any reason to do this.

Thanks for the input. It makes me re-think in terms of forest through the trees. I have primarily been fixed in /dev/sdx1=/boot from
the old grub "requirement". At the moment I am also a little fixed in my filesystem based backup/restore method
where I reduce the size of each on a partition/filesystem basis and not cluttering up something relatively static with something I
might mess up... Not really the case here as I am only slightly curious about seeing what happens say when I build a v3 kernel
on a vanilla rhel6 based distro... I am not planning on multi-distro boot access... Hmmm
===================================================================================
> I think the Ubuntu 8.04 LTS USB stick should work which is what I intend to modify, but I still
> kinda wonder about the update issues surrounding the kernel once the grub version is
> changed...

With grub2 a grub update should cause it to be reinstalled on your boot device.  A kernel or initrd update should cause the config to be rebuilt.  If your distro doesn't get that right, get one that does (obsolete distros aside).

This sounds sane. I'll probably check to see that I am not double grubbed in my software inventory to be safe (at least in my mind 8^)

> Oh, I have also found various fdisk representations e.g. starting block and DOS compatibility
> mode between versions available on installation media and my favorite systemrescueCD to be a bit
> confusing particularly when choosing the start so as to install the grub on a HDD.
=================================================================
How big is your core.img?  It has to fit between the MBR and the first partition.

I'll have to look at that.

Dave



-Mike  (Whoops .. if my mail partition comes out a bit screwy)  
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://cluedenver.org/pipermail/clue/attachments/20120312/3f610898/attachment.html 


More information about the clue mailing list