Hacking on *traffic* Repos used: : implements control plane, has testing stuff in pkg/test/main (iirc). : implements client for xDS - can probably list all code out from there. To see if things are working start the testing control plane from go-control-plane: https://github.com/envoyproxy/envoy/blob/master/api/API_OVERVIEW.md https://github.com/envoyproxy/learnenvoy/blob/master/_articles/service-discovery.md Cluster: A cluster is a group of logically similar endpoints that Envoy connects to. In v2, RDS routes points to clusters, CDS provides cluster configuration and Envoy discovers the cluster members via EDS. # Testing ~~~ sh $ cd ~/src/github.com/envoyproxy/go-control-plane % make integration.xds ~~~ This runs a binary from pkg/test/main. Now we're testing aDS. The script stops, unless you have Envoy installed (which I haven't), but you can run it manually: ~~~ sh ./bin/test --xds=ads --runtimes=2 -debug # for ads ~~~ This fails with `timeout waiting for the first request`, means you're consumer wasn't quick enough in asking for xDS assignments. Use insecure.