[Libguestfs] ovirt VM image to BM

[Richard W.M. Jones]

On Wed, May 18, 2022 at 01:56:36PM +0100, Richard W.M. Jones wrote:
> 
> On Wed, May 18, 2022 at 01:20:27PM +0200, Guilherme De Oliveira Santos wrote:
> > Greetings masters,
> >
> > I got pointed to you guys as experts on smtg I'm struggling with.
> > I'm trying to move an ovirt vm raw image to a bm machine and though
> [bm = baremetal]
> > I could do it successfully using dd (got able to see and work with
> > the partitions and the data fine), I couldn't boot the disk.
> >
> > It may be an issue with drivers (like the virtio drivers), but idk,
> > and I'm wondering if someone has done smtg similar or could help
> > somehow with the process.
> 
> So in IRC we established that it's a RHEL 8.6 guest, and that it
> doesn't get as far as grub.  The virtual machine boots with UEFI and
> the physical machine boots with BIOS which is why grub doesn't work.
> 
> Conversion of a machine from UEFI to BIOS is usually quite tricky.
> Are you sure the baremetal machine doesn't support UEFI booting?
> Almost anything made in the last 10 years should, although you may
> have to adjust the firmware ("BIOS") configuration.
> 
> After that it'll probably not have the right drivers in the initramfs.
> Symptoms would be that it gets to grub, then boots the kernel, but
> fails when mounting the root filesystem.  Luckily this is easier
> to solve - identify which drivers are needed for the target
> hardware and before copying across, run “dracut --add-drivers ..”
> You'll have to read the dracut man page closely.

Update is that after changing the hardware to use UEFI it booted all
the way (a little surprising?)

But the keyboard doesn't work.  This is also surprising because I
*thought* that both virt and baremetal basically use emulated or real
USB keyboard these days.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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