I've just tested it on the latest master, don't see placeholder nic created for the VPC VR.
In addition to the case Murali explained, placeholder nic is being created per Shared network case using VR as DHCP provider. Its done to preserve the same ip address for the case when VR is being expunged/re-created during the network restart/Vrdestroy. As a result of expunge VR its nic is being cleaned up - and ip released - , so we had to make sure that the new VR would get the same ip. More details are in 26b892daf3cdccc2e25711730c7e1efcdec7d2dc, CLOUDSTACK-1771. -Alena. On 10/9/13 2:57 AM, "Murali Reddy" <murali.re...@citrix.com> wrote: >On 09/10/13 11:33 AM, "Darren Shepherd" <darren.s.sheph...@gmail.com> >wrote: > >>Why is a placeholder nic created before the VRs for the VPC are created? >> >>Darren >> > >Generally place holder nic is used in cases where cloudstack uses a subnet >IP from the guest subnet, but ip is not used for any VM nic's. In most of >the external network devices, needs a subnet IP from the guest network >CIDR, cloudstack creates a place holder nic and allocates a subnet ip. > >