Envoy Proxy¶

The envoy probe monitors Envoy by scraping its admin interface (/stats?format=prometheus), surfacing server health, listener downstream connections and requests, and per-cluster upstream metrics.

Quick start¶

probes:
  - name: envoy
    type: envoy
    params:
      endpoint: http://localhost:9901

Parameters¶

Parameter	Default	Description
`endpoint`	`http://localhost:9901`	Envoy admin interface base URL

Metrics¶

Metric	Unit	Description
`senhub.envoy.up`	1	1 when the admin `/stats` endpoint responded successfully
`envoy.server.uptime`	s	Time since the Envoy process started
`envoy.server.memory.allocated`	By	Memory currently allocated by the Envoy process
`envoy.server.connections.active`	{connection}	Active downstream connections across all listeners
`envoy.listener.downstream.connections.active`	{connection}	Active downstream connections per listener
`envoy.cluster.upstream.requests.active`	{request}	Active upstream requests per cluster, tagged with `cluster`
`envoy.cluster.upstream.connections.active`	{connection}	Active upstream connections per cluster

Operational notes¶

The Envoy admin interface is typically bound to 127.0.0.1:9901. If the agent runs on the same host, the default endpoint works without changes.
The admin interface should not be exposed to untrusted networks — it provides access to configuration and health state without authentication.
Cluster-level metrics are tagged with cluster (derived from the envoy_cluster_name Prometheus label).