anchor.diff:      remote:
           cluster_one: <1>
               seeds: 127.0.0.1:9300 <2>
  -            transport.ping_schedule: 30s <3>
           cluster_two: <1>
  -            mode: sniff <4>
  +            mode: sniff <3>
               seeds: 127.0.0.1:9301 <2>
  -            transport.compress: true <5>
  -            skip_unavailable: true <6>
  +            transport.compress: true <4>
  +            skip_unavailable: true <5>
           cluster_three: <1>
  -            mode: proxy <4>
  -            proxy_address: 127.0.0.1:9302 <7>
  +            mode: proxy <3>
  +            proxy_address: 127.0.0.1:9302 <6>
   
   --------------------------------
   <1> `cluster_one`, `cluster_two`, and `cluster_three` are arbitrary _cluster aliases_
  
positive.code: distinguish between local and remote indices.
  <2> The hostname and <<transport-settings,transport port>> (default: 9300) of a
  seed node in the remote cluster.
  <3> A keep-alive ping is configured for `cluster_one`.
  <4> The configured connection mode. By default, this is <<sniff-mode,`sniff`>>, so
  the mode is implicit for `cluster_one`. However, it can be explicitly configured
  as demonstrated by `cluster_two` and must be explicitly configured for
  <<proxy-mode,proxy mode>> as demonstrated by `cluster_three`.
  <5> Compression is explicitly enabled for requests to `cluster_two`.
  <6> Disconnected remote clusters are optional for `cluster_two`.
  <7> The address for the proxy endpoint used to connect to `cluster_three`.
  
  [discrete]
  [[remote-cluster-settings]]
  
negative.code:         "cluster_one": {
            "seeds": [
              "127.0.0.1:9300"
            ]
          },
          "cluster_two": {
            "mode": "sniff",
  