vCloud Director: No routing when Edge and VM are on separate hosts.

jibbajabba

I don't get it. I just setup a test environment. Two hosts, 4 NICs each, two are connected to a dvswitch, two to a standard switch used for ISCSI. Now when I create a VM (manually or from template), I am unable to actually get external connectivity unless the Edge device and VM are on the same host. It doesn't matter which host, so both hosts see, to be working just fine.

This is somewhat baffling ....

Anyone seen this before ? I only found one reference on google, which didn't get any replies / solutions.

jibbajabba

Right, that might have been a facepalm moment. This testing environment is a nested setup to test some upgrade scenarios. The physical host is attached to one particular VLAN. The two virtual hosts are connected to that particular portgroup with 4 NICs. Now silly enough - those virtual nics are connected to the VLAN tagged portgroup, rather than a new portgroup which is a trunk and then tag in the virtual cluster.

Bottom line, vCloud direcetor needs two networks obviously - the external network on VLANxx and the internal network on VLANyy (internal, which is technically the routed external).

Well .. you cannot have two networks with the same VLAN - or in that case, untagged. So I had to make up a VLAN. Because the physical ports aren't trunks, packets coming through the made-up VLAN obviously are being dropped - so no way traffic can be routed between two VLANs when the underlying physical network (even if its a tagged portgroup) is tagged rather than a trunk port.

Hence it only works when both, Edge device and VM, are on the same host.

Well, that is the only explanation I got anyway ...