WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have preserved to ensure that existing links to archives are not broken. The live archive, which contains the latest emails, can be found at http://lists.xen.org/
   
 
 
Xen 
 
Home Products Support Community News
 
   
 

xen-devel

Re: [Xen-devel] [RFC] bootloader improvements

To: Tim Deegan <Tim.Deegan@xxxxxxxxxxxxx>
Subject: Re: [Xen-devel] [RFC] bootloader improvements
From: John Levon <levon@xxxxxxxxxxxxxxxxx>
Date: Fri, 10 Nov 2006 17:25:47 +0000
Cc: xen-devel@xxxxxxxxxxxxxxxxxxx
Delivery-date: Fri, 10 Nov 2006 09:26:19 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxx
In-reply-to: <20061110110527.GA5839@xxxxxxxxxxxxxxxxxxxxx>
List-help: <mailto:xen-devel-request@lists.xensource.com?subject=help>
List-id: Xen developer discussion <xen-devel.lists.xensource.com>
List-post: <mailto:xen-devel@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/cgi-bin/mailman/listinfo/xen-devel>, <mailto:xen-devel-request@lists.xensource.com?subject=unsubscribe>
References: <20061109192017.GA16487@xxxxxxxxxxxxxxxxxxxx> <20061110110527.GA5839@xxxxxxxxxxxxxxxxxxxxx>
Sender: xen-devel-bounces@xxxxxxxxxxxxxxxxxxx
User-agent: Mutt/1.5.9i
On Fri, Nov 10, 2006 at 11:05:27AM +0000, Tim Deegan wrote:

> >     - Make pygrub be the "default" bootloader and understand that
> >       keyword.
> 
> I don't understand why this is needed.  Why not just not set a
> bootloader= option if you want the default?

I don't understand your point. The name and location of 'pygrub' should
be an internal detail unless somebody /wants/ to use a different
bootloader. It's a natural follow-on for the first patch.

> > pygrub-kernel-config
> > pygrub-no-grub
> > 
> >     - The combination of these patches allows pygrub FS code to be
> >       used in a hands-off manner. Note that this can also be used to
> >       fix the problem pygrub currently has with restart, by
> >       specifying the kernel/ramdisk explicitly in the config. The
> >       split between "boot kernel" and "configured kernel" might need
> >       some xen api/lifecycle changes too?
> 
> Hmmm.  I like the idea of splitting the bootloader's suggested
> kernel/etc from the config file's one, but I don't think the bootloader
> should be involved in that at all.  I'd rather have Xend be able to make
> a decision based on all the information from both sources.   This needs
> a bit more thought generally.

Could you expand a bit more on what you mean here?

> >     - Solaris domU's will typically never change the kernel/ramdisk
> >       path they use, except if someone's debugging etc. Add some
> >       logic to pygrub so it knows what to do.
> 
> Autodetecting Solaris seems fine, but from that patch it looks like
> pygrub will always choose Solaris even if there's a grub menu.lst in the
> guest.  I'd prefer that to be the other way around: always use the menu
> file, even if we think we can see Solaris.

There /is/ no menu file on Solaris domU.

> Could this code, instead of just overriding the menu code entirely, just
> add another line to the grub menu that contains the default Solaris
> config?  That way if there's no menu.lst, you get a single-item menu for
> Solaris, and even if there is a menu.lst, you still get the choice of a
> "vanilla" Solaris boot.  Something like:
> 
>   sol_lines = ["title Default Solaris boot",
>                "kernel %s %s" % (sol_krnl, sol_args),
>              "ramdisk /platform/i86pc/boot_archive" ]
>   sol_img = grub.GrubConf.GrubImage(sol_lines)
>   g.cf.images.append(sol_img)

Why? I don't understand why replacing a hands-off method with a load of
interactive gook is a step forward.

regards,
john

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel