anchor.diff:  
   Some users will need or want a DNS name to resolve to their container
   names.  The crunchy-dns container provides the following:
  +
    * listens to a Docker URL or socket for events that would indicate
    a container is created or destroyed
    * implements the consul.io DNS server
  
positive.code: psql -h localhost -p 12000 -U testuser -W testdb
  ....
  
  To shut down the instance, run the following commands:
  ....
  docker stop basic
  ....
  
  To start the instance, run the following commands:
  ....
  docker start basic
  ....
  
  === *master-replica* - Creating a master and replica database cluster
  
negative.code: Those examples are explained below.  The examples make use of
  the local Docker volume driver and data volumes created
  by the *docker create volume* command.  There is a bug however
  that requires the container to run as privileged when in
  SELinux enforcing mode.  See https://github.com/docker/docker/issues/20859[here] for more details.  Also, see link:https://github.com/docker/docker/pull/23024[here].  When this is fixed, you will not need to specify *privileged*
  when starting the examples.
  
  === *basic* - Running a single database container
  