anchor.diff:  
   <<docker,Install {es} with Docker>>.
   
  -Inside a new, empty, directory create the following **four files**:
  +Inside a new, empty directory, create the following four files:
   
   `instances.yml`:
   ["source","yaml"]
  
positive.code:       - xpack.ssl.certificate=$CERTS_DIR/es02/es02.crt
        - xpack.ssl.key=$CERTS_DIR/es02/es02.key
      volumes: ['esdata_02:/usr/share/elasticsearch/data', './certs:$CERTS_DIR']
    wait_until_ready:
      image: docker.elastic.co/elasticsearch/elasticsearch-platinum:{version}
      command: /usr/bin/true
      depends_on: {"es01": {"condition": "service_healthy"}}
  volumes: {"esdata_01": {"driver": "local"}, "esdata_02": {"driver": "local"}}
  ----
  
  <1> Bootstrap `elastic` with the password defined in `.env`. See 
  {stack-ov}/built-in-users.html#bootstrap-elastic-passwords[the Elastic Bootstrap Password].
  <2> Disable verification of authenticity for inter-node communication. Allows
  creating self-signed certificates without having to pin specific internal IP addresses.
  endif::[]
  
  
negative.code:       interval: 30s
        timeout: 10s
        retries: 5
  
    es02:
      container_name: es02
      image: docker.elastic.co/elasticsearch/elasticsearch:{version}
      environment:
        - node.name=es02
        - discovery.zen.minimum_master_nodes=2
        - ELASTIC_PASSWORD=$ELASTIC_PASSWORD
        - discovery.zen.ping.unicast.hosts=es01
        - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
        - xpack.license.self_generated.type=trial
        - xpack.security.enabled=true
        - xpack.security.http.ssl.enabled=true
        - xpack.security.transport.ssl.enabled=true
        - xpack.security.transport.ssl.verification_mode=certificate
  