For the vCloud resource groups, configure networking with vSphere design guidelines in mind. In addition, increase the number of vSphere Distributed Switch (VDS) ports per host from the default value to the maximum of 4096. This improves the scale at which vCloud Director can dynamically create port groups for vCloud networks. For more information about increasing this value see the vSphere Administrator Guide (http://www.vmware.com/support/pubs/vsphere-esxi-vcenter-server-pubs.html).

Increase the maximum transmission unit (MTU) size to 1600 for all devices residing in the transport network for VXLAN or vCloud Director network isolation. This includes physical network devices as well as the VDS. Failure to increase the MTU size causes packet fragmentation, negatively affecting network throughput performance of end-user workloads

vCloud networking considerations are covered in section 5, vCloud Resource Design.