Some problems setting the HTTP Proxy on my Ubuntu

Question

I am a Linux Ubuntu user and I have some problem setting the proxy on my entire system.

I go into the network settings of my Gnome and then I go to the Network Proxy settings mask and then I put my proxy for the *HTTP Proxy** as Manual, then I click on the Applies to the entire system button, it ask me my password and it is finish

The problem is that if I open a shell, the network don't work and I can't ping anyting, infact I obtain only:

andrea@andrea-Studio-1555:~$ ping google.com
PING google.com (173.194.35.7) 56(84) bytes of data.

and the cursor still blink and don't go on...

Why? What can I do to go out with my proxy in the shell?

Answer 1

Ping is ICMP - which is on the "Network Layer". Your proxy is probably supporting only HTTP/HTTPS/FTP etc - which are on "Application Layer". To be able to ping (or send ICMP packets and receive responses) you need to enable ICMP on your firewall.

Please see OSI model: http://en.wikipedia.org/wiki/OSI_model

In other words proxy which you have set up is not designed to proxy ICMP packets as it's "too high".

Also, you say that network doesn't work. Well, it does:

PING google.com (173.194.35.7) 56(84) bytes of data.

As if you don't have google.com in your /etc/hosts then you have got reply form your DNS server so network works.

Answer 2

try wget google it will work, because of http request, ping is ICMP, an other layer in OSI model.

wget google.com

if you want to redirect a network for an app like Apt try to add the following line to the /etc/*.conf file

Acquire::http::Proxy "http://login:password@ServeurProxy:Port";

NTLM Possibility

If it didn't work, you are maybe in some windows network with NTLM auth, install with apt NTLMAPS or CNTLM (or download on their website the .deb). In github search NTLM for other langage stuff. After you have to apply that Tuts to make it works properly.

Search around "ntlm ubuntu apt.conf" in google it is a common problem, you can find other infos. Enjoy :)