How do I configure zone aware routing?

This section describes the specific configuration for the Envoy running side by side with the source service. These are the requirements:

Envoy must be launched with --service-zone option which defines the zone for the current host.
must be set to the source cluster.

Only essential parts are listed in the configuration below for the cluster manager.

Only zone related data is listed in the response below.

The above configuration is necessary for zone aware routing, but there are certain conditions when zone aware routing is not performed.