HTTP proxy settings can be set directly under the network key. This will automatically configure proxy settings for both Docker and System Docker.

#cloud-config
rancher:
  network:
    http_proxy: https://myproxy.example.com
    https_proxy: https://myproxy.example.com
    no_proxy: localhost,127.0.0.1


Note: System Docker proxy settings will not be applied until after a reboot.

To add the HTTP_PROXY, HTTPS_PROXY, and NO_PROXY environment variables to a system service, specify each under the environment key for the service.

#cloud-config
rancher:
  services:
    myservice:
      ...
      environment:
      - HTTP_PROXY
      - HTTPS_PROXY
      - NO_PROXY