How does Ubuntu use apt-get to update the Internet through proxy?

If your company's network architecture is accessed through a proxy server, UBUNTU may encounter problems when using apt-Get updates. Even if you have configured a system-wide proxy server (system wide proxy server ). When executing commands such as apt-Get update, the following error occurs:

407 proxy authentication required

You only need to change the configuration file of APT-Get. modify the content of/etc/APT/apt. conf:

$ CAT/etc/APT/apt. conf
Acquire: http: proxy "http: // username: passowrd @ Proxy: 80 /";
Acquire: ftp: proxy "ftp: // username: password @ Proxy: 80 /";
Acquire: https: proxy "https: // username: password @ Proxy: 80 /";

Username, password, proxy, and port must be modified according to the actual conditions.

In this way, you can update the system.

Reference: http://askubuntu.com/questions/88976/407-proxy-authentication-required