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/
Home Products Support Community News


Re: [Xen-users] Xen 3.4.1: pygrub Error: Boot loader didn't return any

To: Gerry Reno <greno@xxxxxxxxxxx>
Subject: Re: [Xen-users] Xen 3.4.1: pygrub Error: Boot loader didn't return any data!
From: "Fajar A. Nugraha" <fajar@xxxxxxxxx>
Date: Thu, 31 Dec 2009 11:40:59 +0700
Cc: "xen-users@xxxxxxxxxxxxxxxxxxx" <xen-users@xxxxxxxxxxxxxxxxxxx>
Delivery-date: Wed, 30 Dec 2009 20:41:37 -0800
Envelope-to: www-data@xxxxxxxxxxxxxxxxxxx
In-reply-to: <4B3C283E.6010509@xxxxxxxxxxx>
List-help: <mailto:xen-users-request@lists.xensource.com?subject=help>
List-id: Xen user discussion <xen-users.lists.xensource.com>
List-post: <mailto:xen-users@lists.xensource.com>
List-subscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=subscribe>
List-unsubscribe: <http://lists.xensource.com/mailman/listinfo/xen-users>, <mailto:xen-users-request@lists.xensource.com?subject=unsubscribe>
References: <4B3C283E.6010509@xxxxxxxxxxx>
Sender: xen-users-bounces@xxxxxxxxxxxxxxxxxxx
On Thu, Dec 31, 2009 at 11:27 AM, Gerry Reno <greno@xxxxxxxxxxx> wrote:
> I converted a kvm guest to a PV guest converting grub2 to grub and running
> update-grub in the guest but it does not want to start.  I remembered to
> adjust the indexing from hd0,5 in grub2 to hd0,4 in grub legacy but for some
> reason pygrub cannot boot it.  I don't even get a grub prompt.  Can anyone
> see anything wrong with this config?

> bootloader = "/usr/bin/pygrub"
> disk = [ "tap:aio:/var/lib/xen/images/CLOUD-CC-1.img,xvda5,w" ]

First of all, where on earth did you get your conversion instructions from?
If you install it as HVM, and use the same disk image for PV, then you
should've map it as disk. i.e

disk = [ "tap:aio:/var/lib/xen/images/CLOUD-CC-1.img,xvda,w" ]

instead of

disk = [ "tap:aio:/var/lib/xen/images/CLOUD-CC-1.img,xvda5,w" ]

second, AFAIK pygrub doesn't really care about boot sectors or MBR.
That means you could have whatever bootloader originally on the HVM
domU (grub2, extlinux, grub, etc.) and you don't have even have to
install grub or run update-grub to make pygrub works. What you DO
- an active/bootable partition table. This is necessary only if you
map the disk image as disk on domU (i.e. xvda instead of xvda1).
pygrub will then read config from this partition.
- a /boot/grub/menu.lst on the active partition. This file must
contain the correct grub entries.


Xen-users mailing list