Cluster discovery service¶
The cluster discovery service (CDS) is an optional API that Envoy will call to dynamically fetch cluster manager members. Envoy will reconcile the API response and add, modify, or remove known clusters depending on what is required.
Any clusters that are statically defined within the Envoy configuration cannot be modified or removed via the CDS API.
CDS has a statistics tree rooted at cluster_manager.cds. with the following statistics:
|config_reload||Counter||Total API fetches that resulted in a config reload due to a different config|
|update_attempt||Counter||Total API fetches attempted|
|update_success||Counter||Total API fetches completed successfully|
|update_failure||Counter||Total API fetches that failed because of network errors|
|update_rejected||Counter||Total API fetches that failed because of schema/validation errors|
|version||Gauge||Hash of the contents from the last successful API fetch|
|control_plane.connected_state||Gauge||A boolean (1 for connected and 0 for disconnected) that indicates the current connection state with management server|