live migration problems.

[Riccardo Veraldi <Riccardo.Veraldi@cnaf.infn.it>]

Hello,
I have problems with live migration.
I have several VMs in a CentOS 6.2 cluster environment.

When I migrate one virtual machine from nodeA to nodeB the migration 
goes smoothly but
in the same time the VM is migrated an external ping cannot reach the VM.
I ping the VM before migration and after the migration is done ping 
stops to work.
This happens for some VM and does not happen for other VM.
Apparently the VM are configured the same way so I can't understand why 
this is happening.
If I migrate the VM back to the original physical node the ping start 
working again like if the switch did not
realize the VM mac address changed switch port.
To make things work always I Should make a ping from the VM console to 
whatever host and
in this case the arp table is updated on the switch.
The strange thing as I said is that some VM seems to always work after 
migration while other
seems never to work untl they are migrated back to original cluster node.
Any hints or suggestions ?

thank you very much

Rick