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

[Paul Leiber <paul@xxxxxxxxxxxxxxxx>]

Am 05.01.26 um 01:48 schrieb Elliott Mitchell:
> 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.
Hi Elliott,

thanks for the help. As stated in my reply to Nils, I wasn't considering 
that a Debian install should be possible via console.
As for your reference to the Debian wiki, I am afraid that in this 
specific case, it rather has contributed to my brainfog. The site on 
Debian DomU installation only provides an example using HVM [1]. It 
clearly needs updating (as do many other resources on Xen, alas). The 
Debian wiki site on Xen [2] is a bit better, but lacks specific 
information on the DomU installation process. The link to the Xen wiki 
that Nils provided [3] seems to be the best guide on how to install 
Debian when not using xen-tools.
I will likely stick with xen-tools though, as long as it is working. 
It's really convenient to execute one command and get a fully set up 
DomU without interaction with the installer. Too bad it is not 
maintained anymore.
Best regards,

Paul

[1] https://wiki.debian.org/Xen/InstallDebianGuest
[2] https://wiki.debian.org/Xen#Create_simple_domUs
[3] 
https://wiki.xenproject.org/wiki/Debian_Guest_Installation_Using_Debian_Installer