Re: Installing Debian HVM DomU on Xen: Grub installation error

[Elliott Mitchell <ehem+xen@xxxxxxx>]

On Thu, Jan 01, 2026 at 11:37:37PM +0100, Paul Leiber wrote:
> Am 23.12.25 um 12:06 schrieb Paul Leiber:
> > 
> > due to ongoing instabilities with Xen on a Raspberry Pi (seemingly
> > random crashes where I couldn't figure out the cause yet, I suspect
> > networking as the root cause), I am switching to a low-powered x64
> > platform (APU 4D4 with GX-412TC CPU). I already have the same hardware
> > running very stably for a couple of years with Xen for a different
> > purpose.
> > 
> > I now have installed Debian Trixie as a Dom0 on the hardware, and then
> > went through the usual hoops to install Xen on the system, which seems
> > to be running running fine so far.
> > 
> > Then I tried to install a Debian DomU. It seems that things have gotten
> > more complicated than I am used to:
> > 
> > - The xen-tools package with the handy create-xen-image tool is not
> > available for Trixie. Ok, install a Debian HVM instead.
> > - Starting a HVM DomU with networking is not possible without manually
> > installing ipxe-qemu package (bug 1120146 which already has been fixed,
> > but is not in the current release yet [1]).
> > - When running the Debian (I tried both Trixie and Bookworm, with the
> > same result) installer from a netinstall image as HVM DomU, the
> > installer fails while installing grub with error code 1 (last couple of
> > installation log lines below). I couldn't find any related bug so far. I
> > tried both BIOS and UEFI boot methods, with the same outcome.
> > 
> > On the plus side, the issue with the OVMF package seems to have been
> > fixed? [2] At least the installation iso is booting with OVMF out of the
> > box.
> > 
> > I now am stuck and would be grateful for any pointers, specifically:
> > 
> > 1. Does anybody have a hint how to install a Debian Trixie HVM DomU?
> > 2. Does anybody have xen-tools running or another efficient way to
> > create a Trixie PV DomU?
> 
> For future reference: I managed to install Debian Trixie as a DomU. I tried
> starting a DomU by copying a config file from a Windows DomU and starting
> the Debian installation iso with this config. That worked. I guess some
> setting was missing in my initial config file. I didn't do the cross check
> yet, but I suspect that setting hdtype='ahci' did the trick. The generic
> error error message in the Debian installation logs was not very helpful.
> 
> However, I wasn't really happy with the manual HVM installation method,
> therefore I had a closer look on the Debian xen-tools package. The Debian
> package is currently orphaned, but I could quite easily build the package
> from the source code [1]. With the xen-tools package, I could successfully
> install a Trixie DomU in a much more convenient way. I am very happy that
> xen-tools exists and is still working.

I suggest you take a look at Debian's wiki (https://wiki.debian.org/Xen)
as that is nominally supposed to be accurate.  Though looks like some
valuable pieces of information have gone missing.

You likely first want to go to /etc/xen and example the files named
"xlexample.*" for examples of what the actual VM configurations look
like (alas these aren't consistent).  Ones in /etc/xen/auto will be
automatically started after boot.

You almost certainly want to install the `grub-xen-host` package.

For Debian guests you likely want to set `type = "pvh"` and then
`kernel = "/usr/lib/grub-xen/grub-i386-xen_pvh.bin"`.  This gets you a
PVH VM with GRUB as the bootloader.


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