[libvirt] VM Migration with IEEE802.1Qbh and IEEE802.1Qbg

[Martin Kletzander]

On 09/02/2012 01:53 PM, Jagath Weerasinghe wrote:
> Hi All,
> 
> Can a VM connected as IEEE802.1Qbh be migrated to a destination host
> as it were connected as IEEE802.1Qbg? What I wanted to know is, is it
> possible to change the configuration from IEEE802.1Qbh to IEEE802.1Qbg
> on the fly?
> 

IIUC, you want to migrate the guest from host A, where it has a network
interface connected to 802.1Qbh switch, to host B, where it should be
connected to 802.1Qbg switch, right?

I see three possibilities to do that, but unfortunately I cannot say if
these will work.

If the guest has <interface type='network'> and that network has
<virtualport type='802.1Qbh'> on host A and <virtualport
type='802.1Qbg'> on host B, that might be working as-is.

If the guest has <virtualport type='802.1Qbh'> specified in its
<interface>, you should be able to change the type using migrate hook
[1] on host B.

There should be one more option in case the <virtualport> is specified
in the guest's <interface>. According to the docs [2], when no "type="
is specified for the <virtualport> element, this should be
auto-completed on the domain startup, but that's most probably not
applicable for your situation (migration).

Is that what you wanted to know?

Martin

[1] http://libvirt.org/hooks.html#qemu_migration
[2] http://libvirt.org/formatdomain.html#elementsNICSVirtual