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:       - discovery.zen.minimum_master_nodes=2
        - ELASTIC_PASSWORD=$ELASTIC_PASSWORD <1>
        - "ES_JAVA_OPTS=-Xms512m -Xmx512m"
        - xpack.security.http.ssl.enabled=true
        - xpack.security.transport.ssl.enabled=true
        - xpack.security.transport.ssl.verification_mode=certificate <2>
        - xpack.ssl.certificate_authorities=$CERTS_DIR/ca/ca.crt
        - xpack.ssl.certificate=$CERTS_DIR/es01/es01.crt
        - xpack.ssl.key=$CERTS_DIR/es01/es01.key
  
negative.code: ["source","yaml",subs="attributes"]
  ----
  version: '2.2'
  
  services:
    es01:
      container_name: es01
  