libvirt users - Mar 2014 - Re: how to disable vnet_hdr through libvirt

Hi,

I am using libvirt and virsh to create my VM on KVM. It works fine. However, I
need to turn off vnet_hdr for virtio interface.

Does anyone know how to do it through libvirt?

Thanks.

On Fri, Feb 28, 2014 at 07:11:13PM +0000, Jianfeng Tang
wrote:
> Hi,
> 
> I am using libvirt and virsh to create my VM on KVM. It works fine.
> However, I need to turn off vnet_hdr for virtio interface.
> 
> Does anyone know how to do it through libvirt?
There's no support for disabling it - if we detect a host which supports
it, it will be unconditionally enabled.

Regards,
Daniel
-- 
|: http://berrange.com      -o-    http://www.flickr.com/photos/dberrange/ :|
|: http://libvirt.org              -o-             http://virt-manager.org :|
|: http://autobuild.org       -o-         http://search.cpan.org/~danberr/ :|
|: http://entangle-photo.org       -o-       http://live.gnome.org/gtk-vnc :|

Thank you Daniel. How difficult to extend libvirt for this? One critical
application on my VM needs to turn vnet_hdr off.
I can switch to use qemu directly. However, in that way I will lose all
the nice things provided by libvirt.

Thanks,
~Jianfeng

On 3/3/14 3:53 AM, "Daniel P. Berrange" <berrange@redhat.com>
wrote:
>On Fri, Feb 28, 2014 at 07:11:13PM +0000, Jianfeng Tang wrote:
>> Hi,
>> 
>> I am using libvirt and virsh to create my VM on KVM. It works fine.
>> However, I need to turn off vnet_hdr for virtio interface.
>> 
>> Does anyone know how to do it through libvirt?
>
>There's no support for disabling it - if we detect a host which supports
>it, it will be unconditionally enabled.
>
>Regards,
>Daniel
>-- 
>|: http://berrange.com      -o-
>http://www.flickr.com/photos/dberrange/ :|
>|: http://libvirt.org              -o-
>http://virt-manager.org :|
>|: http://autobuild.org       -o-
>http://search.cpan.org/~danberr/ :|
>|: http://entangle-photo.org       -o-
>http://live.gnome.org/gtk-vnc :|