[ovs-discuss] Changing OVS versions in XenServer

[David Erickson]

On 9/7/2011 7:10 PM, Justin Pettit wrote:
> On Sep 7, 2011, at 5:29 PM, David Erickson wrote:
>
>> Is there a specific procedure for moving between OVS versions in XenServer?  I've done this a few times, and frequently I find myself in a situation where the xenbr0 device has completely disappeared, and I couldn't find a way to restore it other than re-installing Xen.  In particular I believe I've had success doing an rpm upgrade to newer Xen versions, however I think any time I've removed the OVS rpm's to install an older version I've lost the xenbr0 instance.  Any tips/suggestions are welcome.
>
> Are you losing xenbr0 after you've done the uninstall and before the new install?  If so, you probably should switch the networking back-end to "bridge" before you do the uninstall:
>
> 	xe-switch-network-backend bridge
>
> After you've done the install, switch it back to OVS:
>
> 	xe-switch-network-backend vswitch
>
> As you indicated, a pure RPM upgrade of OVS should work fine.
>
> Let us know if I've misunderstood.

I was able to reproduce this.  Starting with XenServer release 
5.6.100-39215p and an installed version of OVS 1.2.1, I switched the 
backend to bridge, rebooted, removed the OVS rpms, rebooted, installed 
the original XS OVS rpm openvswitch-1.0.2-82.1943.i386.rpm, switched the 
backend to openvswitch, rebooted, and xenbr0 was gone.  Any ideas?

Thanks,
-David