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I am using a proxy to connect to internet. I can use firefox and software center. but can not ping google. when I try it says

ping google.com

ping: unknown host google.com

I have tried with ip address also. it says Destination Host Unreachable.

please help. Thanks in advance.

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That doesn't matter in this case... –  the_Seppi Mar 2 '14 at 15:44
yes, You are right. I found that I am also suffering from same problem. –  g_p Mar 2 '14 at 15:46
If you're accessing through proxy.. then have you tried applying proxy system wide under network... :) –  AzkerM Mar 2 '14 at 15:50
Little strange problem. I can ping when I am connected using ppp interface but can't when using my samsung wave mobile wifi hotspot. –  g_p Mar 2 '14 at 15:55
I guess the phone accesses the internet via 3G etc. so you don't need the proxy there –  the_Seppi Mar 3 '14 at 17:04

2 Answers 2

up vote 1 down vote accepted

For bash commands you have to set the proxy seperately. For this, you have to set a environment variable, e.g.:

ping google.com    # can't resolve, no proxy set
export http_proxy=proxy.example.com:1234
ping google.com    # works, proxy set for this bash session.

Replace the address and the port with your proxy configuration. If you're always behind this proxy, add the export http_proxy... command to ~/.bashrc so it gets executed every time you start a new bash session.

Or to execute a single command with proxy settings and without setting environment variables, use env, e.g.:

env http_proxy=proxy.example.com:1234 ping google.com
sudo env http_proxy=proxy.example.com:1234 apt-get install cowsay

To use other services, e.g. HTTPS or FTP you have to set different variables:

export https_proxy=proxy.example.com:1234
export ftp_proxy=proxy.example.com:1234
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Try this:

Open a terminal. Ctrl + Alt + T

Run it:

$ sudo -i
# nano /etc/bash.bashrc

Put the following lines in the file:

export http_proxy=http://my_proxy_server:3128/
export https_proxy=http://my_proxy_server:3128/
export ftp_proxy=http://my_proxy_server:3128/
export socks_proxy=socks://my_proxy_server:3128/

Ctrl + U, paste. Ctrl + O, save file. Ctrl + X, close nano.

$ sudo -i
# nano /etc/environment

Put the following lines in the file


Ctrl + U, paste. Ctrl + O, save file. Ctrl + X, close nano.

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