When CDO mode is enabled in a transport zone, it will create a hidden logical switch called a CDO logical switch to handle BUM traffic when the control plane connectivity is lost. The CDO logical switch creates a Global VTEP, which is maintained by all ESXi hosts. All ESXi hosts in the transport zone join the CDO logical switch, and one of the NSX controller nodes will be responsible for updating the Global VTEP information to all hosts on the vSphere cluster associated to that transport zone. The Global VTEP information is populated when the control plane connectivity is up and utilized when the control plane connectivity is lost so the BUM traffic can still be handled.
The BUM traffic is replicated to the entire transport ...
