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Ubuntu – How to fix update errors for a server behind of a proxy

If you’re behind of a proxy server and the IP address has changed (or proxy it’s a new node in your network topology) then probably when you’re trying to update your binaries then you’ll get a list of errors.

This happens because you’re unable to connect to Ubuntu mirrors. In order to fix this issue you have to edit apt.conf file settings.
– Check the proxy settings in in apt.conf file:

– Update the new proxy IP and port (ex.

If you need user and password for logging to the Proxy server this can be achieved in most cases by using the following layout.
Acquire::http::Proxy "http://username:password@your_proxy_address:proxy_port";

– Finally you may enjoy running the update commands: