Configure Docker to use a proxy server

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If your container needs to use an HTTP, HTTPS, or FTP proxy server, you can configure it in different ways:

• In Docker 17.07 and higher, you can configure the Docker client to pass proxy information to containers automatically.

• In Docker 17.06 and earlier versions, you must set the appropriate environment variables within the container. You can do this when you build the image (which makes the image less portable) or when you create or run the container.

Configure the Docker client

1. On the Docker client, create or edit the file ~/.docker/config.json in the home directory of the user that starts containers. Add JSON similar to the following example. Substitute the type of proxy with httpsProxy or ftpProxy if necessary, and substitute the address and port of the proxy server. You can also configure multiple proxy servers simultaneously.

   You can optionally exclude hosts or ranges from going through the proxy server by setting a noProxy key to one or more comma-separated IP addresses or hosts. Using the * character as a wildcard for hosts and using CIDR notation for IP addresses is supported as shown in this example:

   {
    "proxies":
    {
      "default":
      {
        "httpProxy": "http://192.168.1.12:3128",
        "httpsProxy": "http://192.168.1.12:3128",
        "noProxy": "*.test.example.com,.example2.com,127.0.0.0/8"
      }
    }
   }
   

   Save the file.

2. When you create or start new containers, the environment variables are set automatically within the container.

Use environment variables

Set the environment variables manually

When you build the image, or using the --env flag when you create or run the container, you can set one or more of the following variables to the appropriate value. This method makes the image less portable, so if you have Docker 17.07 or higher, you should configure the Docker client instead.