[Systemroles] Having some issues

Hey , 1.I'm having some issue while trying to run the integration tests for the network role , it happens when the checkpoint is created , I receive a dialog box which says System policy prevents the creation of a checkpoint or its rollback and so nm is unable to create a checkpoint . 2.When I'm running the example tests, the hosts are unreachable 3.I'm having a bit of trouble in setting up virtual interfaces to make some tests, what would be the best way to do it ? Any help would be greatly appreciated. Thanks, Harsh