vPC config not correct when using apic_provision_infra=True and apic_provision_hostlinks=True

[tomflynn]

Wiped my fabric and restarted neutron. All switch/interface policies were created and attached hypervisors correctly appeared under the VMM on the UI. Further investigation showed that the vPC policies had not been downloaded to the leaf and the compute hosts had actually only connected and downloaded policies from one side of the vPC pair.

For the vPC config to work the nodes in apic_vpc_pairs need to be explicitly paired on the APIC using an 'Explicit VPC Protection Group'. (found at Fabric->Access Policies->Switch Policies->Policies on the UI)

NOTE: That after making this change you'll have to ifdown/ifup the bond interface on the compute host to get a new DHCP address

Sample POST (using name and ID 1 and pairing nodes 101 and 102)

method: POST url: https:///api/node/mo/uni/fabric/protpol/expgep-1.json
body: {"fabricExplicitGEp":{"attributes":{"dn":"uni/fabric/protpol/expgep-1","name":"1","id":"1","rn":"expgep-1","status":"created"},"children":[{"fabricNodePEp":{"attributes":{"dn":"uni/fabric/protpol/expgep-1/nodepep-101","id":"101","status":"created","rn":"nodepep-101"},"children":[]}},{"fabricNodePEp":{"attributes":{"dn":"uni/fabric/protpol/expgep-1/nodepep-102","id":"102","status":"created","rn":"nodepep-102"},"children":[]}},{"fabricRsVpcInstPol":{"attributes":{"tnVpcInstPolName":"default","status":"created,modified"},"children":[]}}]}}