vMotion with a Virtual Intranet

[gesturgis]

Hey folks,

I wonder if this is possible:

We have a group of systems that are connected to a "virtual intranet", i.e. a vSwitch that is not connected to a physical adapter.  One of the systems is a router that has two NICs (obviously) and one of these is connected to a vSwitch that is connected to the physical adapter.

Is there a way to set up a configuration so that I can vMotion these systems?  I thought maybe I could just set up the same port group on each of the ESX cluster hosts and then intranet communications would go over the vmk interface, but that does not appear to work.

Any help?

Thanks,

Eddy

[marcelo_soares]

You will only be able to vMotion the VMs that are on the vSwitch without uplinks if you have a router on each ESX. The network traffic of a vswitch only leaves the ESX with an uplink - there is no other way.

[rickardnobel]

gesturgis wrote:

We have a group of systems that are connected to a "virtual intranet", i.e. a vSwitch that is not connected to a physical adapter. 

I think that VMware will try to make sure to never "break" anything from the VMs point of view with vMotion. If you have several VMs on an internal switch and one of those VMs by magic (vMotion) just disappears then any internal traffic flow will break, which is likely why this is not allowed.

[iw123]

If Ive read correctly, I dont see any reason why you couldnt vmotion these machines from one host to another, providing vmotion was configured correctly and the port groups were named the same on each host.

If you are using a router virtual machine to get off the internal network however, you would have to vmotion all the machines on that network, along with the router at the same time otherwise those virtual machines on the internal network will lose connectivity as soon as the router is vmotioned.

Why not have a non routed vlan in place of the internal network?  

[rickardnobel]

It is not allowed to vMotion a VM away from a vSwitch with no vmnics attached, only cold migrations could be done.

This KB article explains a way to override this:

http://kb.vmware.com/kb/1003832

[gesturgis]

I wonder if I could connect this port group up to a physical adapter even though no network traffic would actually traverse that NIC (all traffic would be within the vSwitch or out through the router VM).  Then, if I ever vMotioned those systems, I would have to make sure that I vMotioned all of them at once.

Any other suggestions?

[gesturgis]

Ian wrote:

Why not have a non routed vlan in place of the internal network?  

If I'm understanding your question correctly:  Because we need to route to those systems.