The contents of the --locality-advertise-addr flag never actually get plumbed into the server/gossip code, meaning that the feature almost certainly doesn't work.

The localityAddress arg to Node.start is unused:

The NodeDescriptor.LocalityAddress field never actually gets set anywhere in our code:
https://sourcegraph.com/github.com/cockroachdb/cockroach@master/-/blob/pkg/roachpb/metadata.pb.go#L166:2=&tab=references

That should be fixed and the feature tested end-to-end.