[ovirt-users] Impact of changing VLAN of ovirtmgmt in the Data Center?

[Edward Haas]

On Fri, Feb 26, 2016 at 2:51 AM, Garry Tiedemann
<garrytiedemann at networkvideo.com.au> wrote:
> Hi everyone,
>
> In Data Centers > (Name) > Networks section of the Ovirt GUI, network
> definitions include the VLAN IDs.
> In my case, the VLAN ID of ovirtmgmt has been empty (meaning VLAN 1) since I
> built it; it's always been wrong.
>
> My hypervisor hosts' ovirtmgmt bridges are actually in VLAN 20.
>
> An error message alerted me to this mismatch a few days ago.
>
> None of my production VMs are on VLAN 1, or VLAN 20, but I'd like to confirm
> if it's safe to change this.
>
> Can changing the VLAN ID of ovirtmgmt within Data Center > Networks impact
> VMs from other VLANs?
>
> I see no reason why it should be a problem. We just need some certainty on
> that point.
>
> Thankyou in advance for answers.
>
> Regards,
>
> Garry
>
> PS This is a briefer and clearer re-statement of the question I asked a
> couple of days ago.
> _______________________________________________

Hello Garry,

If you have other networks for the VM/s, these should not be affected
by such a change.
The risk is in loosing the management network (ovirtmgmt) on your
nodes, including Engine.. But if you know that all nodes (including
Engine) are connected using a VLAN now and the switch uses a trunk
port, you should be ok.
If the node will fail to communicate with Engine after the change,
they will attempt a revert to the last known configuration, reducing
the risk of loosing them.

Note that when you set the network VLAN ID, Engine will send a request
to ALL nodes that have the network for setting up the VLAN.
You need to make sure that the switch port connected to the physical
interface is a trunk and can forward the specified tag ID.
(you did specify something about untagged packets that are classified
to your VLAN ID, that was unclear to me)

If you already managed to perform the change, please share your
results and insights.

Thanks,
Edy.