Management Server ----------------- .. _config_overview_mgmt_con_issues: Management Server Unreachability ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ When an Envoy instance loses connectivity with the management server, Envoy will latch on to the previous configuration while actively retrying in the background to reestablish the connection with the management server. Envoy debug logs the fact that it is not able to establish a connection with the management server every time it attempts a connection. :ref:`connected_state ` statistic provides a signal for monitoring this behavior. .. _management_server_stats: Statistics ^^^^^^^^^^ Management Server has a statistics tree rooted at *control_plane.* with the following statistics: .. csv-table:: :header: Name, Type, Description :widths: 1, 1, 2 connected_state, Gauge, A boolean (1 for connected and 0 for disconnected) that indicates the current connection state with management server rate_limit_enforced, Counter, Total number of times rate limit was enforced for management server requests pending_requests, Gauge, Total number of pending requests when the rate limit was enforced .. _subscription_statistics: xDS subscription statistics ^^^^^^^^^^^^^^^^^^^^^^^^^^^ Envoy discovers its various dynamic resources via discovery services referred to as *xDS*. Resources are requested via :ref:`subscriptions `, by specifying a filesystem path to watch, initiating gRPC streams or polling a REST-JSON URL. The following statistics are generated for all subscriptions. .. csv-table:: :header: Name, Type, Description :widths: 1, 1, 2 config_reload, Counter, Total API fetches that resulted in a config reload due to a different config init_fetch_timeout, Counter, Total :ref:`initial fetch timeouts ` 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 update_time, Gauge, Timestamp of the last successful API fetch attempt as milliseconds since the epoch. Refreshed even after a trivial configuration reload that contained no configuration changes. 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