instruction: Create a comprehensive Dockerfile for networking applications with best practices
output: ```dockerfile
  from the my-net network.
  
  $ docker network disconnect my-net my-nginx
  Use IPv6 in a user-defined bridge networkWhen you create your network, you can specify the --ipv6 flag to enable IPv6.
  
  $ docker network create --ipv6 --subnet 2001:db8:1234::/64 my-net
  If you do not provide a --subnet option, a Unique Local Address (ULA) prefix
  will be chosen automatically.IPv6-only bridge networksTo skip IPv4 address configuration on the bridge and in its containers, create
  the network with option --ipv4=false, and enable IPv6 using --ipv6.
  
  $ docker network create --ipv6 --ipv4=false v6net
  IPv4 address configuration cannot be disabled in the default bridge network.Use the default bridge networkThe default bridge network is considered a legacy detail of Docker and is not
  recommended for production use. Configuring it is a manual operation, and it has
  technical shortcomings.Connect a container to the default bridge networkIf you do not specify a network using the --network flag, and you do specify a
  network driver, your container is connected to the default bridge network by
  default. Containers connected to the default bridge network can communicate,
  but only by IP address, unless they're linked using the
  legacy --link flag.Configure the default bridge networkTo configure the default bridge network, you specify options in daemon.json.
  Here is an example daemon.json with several options specified. Only specify
  the settings you need to customize.
  
  {
   "bip": "192.168.1.1/24",
   "fixed-cidr": "192.168.1.0/25",
   "mtu": 1500,
   "default-gateway": "192.168.1.254",
   "dns": ["10.20.1.2","10.20.1.3"]
  }In this example:The bridge's address is "192.168.1.1/24" (
  ```