Libguestfs - Oct 2018 - Re: virt-builder fail with "bridge ‘virbr0’ not found" (fixed by LIBGUESTFS_BACKEND=direct ?!)

On Wed, Oct 10, 2018 at 10:18 AM Pino Toscano <ptoscano@redhat.com> wrote:
> On Tuesday, 9 October 2018 20:16:04 CEST Nir Soffer wrote:
> > I'm trying to build fedora-27 image for testing uploads:
> >
> > $ virt-builder fedora-27 -o /var/tmp/fedora-27.img
> > ...
> > [  25.2] Opening the new disk
> > virt-builder: 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 _SETTINGS=network_bridge=<bridge name>
>
> The libvirt backend uses a network bridge on the host to setup the
> networking in the guest, which is enabled by default in virt-builder.
>
OK, now it is clear why bypassing libvirt avoids this issue.

So maybe I'm missing some libvirt package required for creating the
bridge?

libvirt is installed by vdsm, which requires:
libvirt-client
libvirt-daemon-config-nwfilter
libvirt-daemon-kvm
libvirt-lock-sanlock
libvirt-python

>
> > I don't want to add bridges to my new fresh oVirt test host, and
> > remember that this used to work previously without the bridge.
>
> "used to work" which version with?

What was available in Fedora 28 2-3 month ago. The vm used for
running this was lost, so I don't have more specific info.

> And which version are you using now?
>
$ rpm -q libguestfs-tools-c
libguestfs-tools-c-1.38.4-1.fc28.x86_64

 Nir

On Wed, Oct 10, 2018 at 02:27:44PM +0300, Nir Soffer
wrote:
> On Wed, Oct 10, 2018 at 10:18 AM Pino Toscano <ptoscano@redhat.com>
wrote:
> 
> > On Tuesday, 9 October 2018 20:16:04 CEST Nir Soffer wrote:
> > > I'm trying to build fedora-27 image for testing uploads:
> > >
> > > $ virt-builder fedora-27 -o /var/tmp/fedora-27.img
> > > ...
> > > [  25.2] Opening the new disk
> > > virt-builder: 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 _SETTINGS=network_bridge=<bridge name>
> >
> > The libvirt backend uses a network bridge on the host to setup the
> > networking in the guest, which is enabled by default in virt-builder.
> >
> 
> OK, now it is clear why bypassing libvirt avoids this issue.
> 
> So maybe I'm missing some libvirt package required for creating the
> bridge?
> 
> libvirt is installed by vdsm, which requires:
> libvirt-client
> libvirt-daemon-config-nwfilter
> libvirt-daemon-kvm
> libvirt-lock-sanlock
> libvirt-python
virbr0 is provided by the libvirt default virtual network, which
sets up NAT based forwarding

VDSM doesn't want this network connectivity so it doesn't install
the libvirt default network, hence you don't have any virbr0.

You can get it by installing the libvirt-daemon-config-network RPM


Regards,
Daniel
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On Wed, Oct 10, 2018 at 2:49 PM Daniel P. Berrangé <berrange@redhat.com>
wrote:
> On Wed, Oct 10, 2018 at 02:27:44PM +0300, Nir Soffer wrote:
> > On Wed, Oct 10, 2018 at 10:18 AM Pino Toscano
<ptoscano@redhat.com>
> wrote:
> >
> > > On Tuesday, 9 October 2018 20:16:04 CEST Nir Soffer wrote:
> > > > I'm trying to build fedora-27 image for testing uploads:
> > > >
> > > > $ virt-builder fedora-27 -o /var/tmp/fedora-27.img
> > > > ...
> > > > [  25.2] Opening the new disk
> > > > virt-builder: 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 _SETTINGS=network_bridge=<bridge name>
> > >
> > > The libvirt backend uses a network bridge on the host to setup
the
> > > networking in the guest, which is enabled by default in
virt-builder.
> > >
> >
> > OK, now it is clear why bypassing libvirt avoids this issue.
> >
> > So maybe I'm missing some libvirt package required for creating
the
> > bridge?
> >
> > libvirt is installed by vdsm, which requires:
> > libvirt-client
> > libvirt-daemon-config-nwfilter
> > libvirt-daemon-kvm
> > libvirt-lock-sanlock
> > libvirt-python
>
> virbr0 is provided by the libvirt default virtual network, which
> sets up NAT based forwarding
>
> VDSM doesn't want this network connectivity so it doesn't install
> the libvirt default network, hence you don't have any virbr0.
>
> You can get it by installing the libvirt-daemon-config-network RPM
>
So maybe libguestfs-tools-c should depend on it?

Nir