How can I check which applications are using internet? How to block internet accessing one particular application? Is there any GUI tool that exist for it in Ubuntu Software Centre? Thanks in advance!

  • 1
    Do you need something like a firewall? Try gUFW from the Software Center.
    – Timo
    Feb 16, 2012 at 14:06
  • 1
    It is probably not possible to block a specific application without resorting to serious command-line geekery. You can use trickler from software center to limit an application's bandwidth usage, but it is also a command-line utility (use like: alt+F2 and enter trickler -d 1 -u 1 application).
    – taneli
    Feb 17, 2012 at 13:15
  • 1
    it is trickle not trickler
    – Tachyons
    Feb 18, 2012 at 10:01

5 Answers 5


lsof -i will list the applications that are accessing the network. There are some helpful examples in the man page but you might also want to look at Track network connections with LSOF on Linux.


I found very useful next command that show only the names of applications that use internet connection (create internet traffic) at the moment:

netstat -lantp | grep -i stab | awk -F/ '{print $2 $3}' | sort | uniq

Source: Show apps that use internet connection at the moment (Multi-Language).


To see which application is using data, try the NetHogs application from the eponymous package nethogs in Ubuntu’s “Universe” repository or from source.


In addition to lsof -i which will list applications that have open network sockets as Richard mentioned, you can also install ufw and gufw which are the Uncomplicated FireWall and the GUI program that manages it. I haven't used either of these since 8.04 since I mostly use ubuntu internal to my own network, but they should have options for that. iptables is also a very popular firewall.


You can get the list of listening applications by using UFW using the following command.

sudo ufw show listening

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .