Error Creating vShield Edge Device for Org vDC

I'm setting up an evaluation cloud, as per the vCloud Director 5.1 Evaluation Guide.  I've hit a snag while trying to set up the edgeGateway for my org vDC.

Here's the error:

Deployment of edge gateway coke_edge_gateway failed.

org.springframework.web.client.ResourceAccessException: I/O error: No route to host; nested exception is java.net.NoRouteToHostException: No route to host

I don't even know what host this is referring to.