Ubuntu: system wide proxy settings

• edit /etc/bash.bashrc

  export http_proxy=http://192.168.1.100:8000/
  export https_proxy=http://192.168.1.100:8000/
  export ftp_proxy=http://192.168.1.100:8000/
  export no_proxy=localhost,127.0.0.0/8,192.168.0.0/16,*.somedomain.org,172.23.65.*