Libguestfs - Aug 2016 - Re: [libvirt-users] couple of questions about virt-v2v

[Best to ask these questions on the libguestfs mailing list.  You
don't have to subscribe]

On Wed, Aug 31, 2016 at 03:18:32PM +0100, cmc wrote:
> Hi,
> 
> I have two questions about virt-v2v that I hope someone could help with.
> 
> 1. I have a host that I use to export VMs from VMWare to oVirt, as the RHEL
> 7 version of virt-v2v does not support W2012.
Please try this version:
https://people.redhat.com/~rjones/libguestfs-RHEL-7.3-preview/
> When I run the
> conversion/export (-o ovirt -os ovirt-srv:/mnt/export) it looks for a
> bridge on the host I'm running the export for. What does it need the
bridge
> on the local host for?
What's the actual error?
> 2. When I run a conversion of a W2012 host, it reports:
> 
> "virt-v2v: warning: Neither rhev-apt.exe nor vmdp.exe can be found. 
Unable
> to install one of them.
> virt-v2v: warning: there is no QXL driver for this version of Windows (6.2
> x86_64).  virt-v2v looks for this driver in /usr/share/virtio-win"
They are included in virt-v2v at the link above.
> I can't find these two exe files. I've installed the
ovirt-guest-tools-iso
> for FC23, and symlinked the mounted ISO to /usr/share/virtio-win, and
> though the two files it is looking for are not on that ISO, I thought it
> might help (it doesn't).
> 
> Can virt-v2v install such drivers, or should this just be done manually
> from within the guest?
Yes virt-v2v can install drivers.  You need the virtio-win package
from RHEL 7, since the WHQL'd drivers are not freely redistributable
(or at least, the situation is complicated).

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-df lists disk usage of guests without needing to install any
software inside the virtual machine.  Supports Linux and Windows.
http://people.redhat.com/~rjones/virt-df/

Hi Rich,

Thanks, I'll see if oVirt supports 7.3 yet.

> What's the actual error?
>
-------------8<------------

virt-v2v: error: libguestfs error: bridge 'virbr0' not found.  Try
running:

  brctl show

to get a list of bridges on the host, and then selecting the
bridge you wish the appliance network to connect to using:

  export LIBGUESTFS_BACKEND_SETTINGS=network_bridge=<bridge name>

You may also need to allow the bridge in /etc/qemu/bridge.conf.
For further information see guestfs(3).

-------------8<------------

I got around this by just running 'brctl addbr virbr0', but was curious
as
to why it needed a bridge on a host it wasn't going to run on. I
couldn't
find the man page for guestfs(3)

> Yes virt-v2v can install drivers.  You need the virtio-win package
> from RHEL 7, since the WHQL'd drivers are not freely redistributable
> (or at least, the situation is complicated).
>
ok, cheers, I'll get those installed.

-C

Rich.
>
> --
> Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~
> rjones
> Read my programming and virtualization blog: http://rwmj.wordpress.com
> virt-df lists disk usage of guests without needing to install any
> software inside the virtual machine.  Supports Linux and Windows.
> http://people.redhat.com/~rjones/virt-df/
>

On Wed, Aug 31, 2016 at 07:28:05PM +0100, cmc wrote:
> Hi Rich,
> 
> Thanks, I'll see if oVirt supports 7.3 yet.
> 
> 
> > What's the actual error?
> >
> 
> -------------8<------------
> 
> virt-v2v: error: libguestfs error: bridge 'virbr0' not found.  Try
running:
> 
>   brctl show
> 
> to get a list of bridges on the host, and then selecting the
> bridge you wish the appliance network to connect to using:
> 
>   export LIBGUESTFS_BACKEND_SETTINGS=network_bridge=<bridge name>
> 
> You may also need to allow the bridge in /etc/qemu/bridge.conf.
> For further information see guestfs(3).
> 
> -------------8<------------
> 
> I got around this by just running 'brctl addbr virbr0', but was
curious as
> to why it needed a bridge on a host it wasn't going to run on. I
couldn't
> find the man page for guestfs(3)
The short answer is that you need to install the
``libvirt-daemon-driver-network'' package (RHEL), or the
``libvirt-daemon-config-network'' package (Fedora).
Or you can avoid using libvirt at all by setting:
export LIBGUESTFS_BACKEND=direct

The long answer is that we have to choose a bridge name in order to
get libvirt to give us a network, but there is no obvious choice of
bridge name so we pick "virbr0" (which happens to be the name of the
libvirt "default" network).  There's not really any good way to
choose
the right bridge name, since it depends on your local network config
and the phase of the moon.  So it's a bug / shortcoming in libvirt.

The very long answer is:
https://bugzilla.redhat.com/show_bug.cgi?id=1148012

BTW randomly creating the bridge as you did might get you past the
error, but probably won't work if virt-v2v actually needs to use the
network. YMMV.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-p2v converts physical machines to virtual machines.  Boot with a
live CD or over the network (PXE) and turn machines into KVM guests.
http://libguestfs.org/virt-v2v