Health check filter architecture overview
This filter should be configured with the type URL type.googleapis.com/envoy.extensions.filters.http.health_check.v3.HealthCheck.
v3 API reference
Note that the filter will automatically fail health checks and set the
x-envoy-immediate-health-check-fail header on all responses (both
health check and normal requests) if the /healthcheck/fail admin endpoint has been called. (The
/healthcheck/ok admin endpoint reverses this