WAN Federation with mesh gateways

Hello,

I’m relatively new to consul, and I’m trying to figure out how to wan join tow data centers through a gateway, meaning consul servers in dc1 have no serf_wan and RPC direct connectivity to consul servers in dc2, in other words if I have a 5 server nodes cluster in each DC I don’t wanna expose 10 different ports on each WAN IP,
in here there is a mention of -expose-servers which I’m guessing is necessary but it doesn’t explain how to actually do it.

And in this very good demo demo-consul-service-mesh/gateways at master · nicholasjackson/demo-consul-service-mesh · GitHub , the two consul servers are wan joined directly not via the gateway