prometheus/server/target/static/etcd.yml

parameters:
  _param:
    prometheus_etcd_host: ${_param:haproxy_bind_address}
    prometheus_etcd_port: 4001
  prometheus:
    server:
      target:
        static:
          etcd:
            enabled: true
            endpoint:
            - address: ${_param:prometheus_etcd_host}
              port: ${_param:prometheus_etcd_port}