Why is apt-get always using proxy, although no proxy is configured?

I'm using a script to replace different configuration files in order to easily switch between proxy and non-proxy environements. The problem was that I replaced the proxy apt.conf file with an empty apt.conf file, which apt then ignored.

After writing Acquire::http::Proxy "false"; into the apt.conf it worked without proxy :)

Sometimes, there are proxy environment variables that are still set.

To find out, do the following command:

env | grep proxy

If you see some output, for example:

http_proxy=http://127.0.0.1:1234/

Then you'll need to unset this variable.

To do so, execute the following command:

unset http_proxy

Follow the same approach for all the other entries, such as https_proxy.

If you do not want apt-get to use a proxy, use apt-get as:

sudo apt-get -o Acquire::http::proxy=false <update/install>