cannot do sudo wireshark - Gtk-WARNING **: cannot open display:

[terapin]

When I launch wireshark(from k-menu..run, or from the command line) it loads but doesn't list interfaces unless I do sudo wireshark or I suppose if I do su then wireshark. That's fine.
But sudo wireshark or su<ENTER>wireshark<ENTER> isn't working.

It worked yesterday but now when I try, I get this error






knoppix@Microknoppix:~$ su root
root@Microknoppix:/home/knoppix# wireshark
No protocol specified

(wireshark:4986): Gtk-WARNING **: cannot open display: :0
root@Microknoppix:/home/knoppix# su knoppix
knoppix@Microknoppix:~$ sudo wireshark
No protocol specified

(wireshark:5038): Gtk-WARNING **: cannot open display: :0
knoppix@Microknoppix:~$

[Werner P. Schulz]

Do not run wireshark as user "root"!
Read some documentations about wireshark. Your problem isn't a Knoppix problem.

[terapin]

Thanks. I got it to work since some days back. For the record it was most likely this solution that I used

http://ask.wireshark.org/questions/7523/ubuntu-machine-no-interfaces-listed
$ sudo apt-get install wireshark
$ sudo dpkg-reconfigure wireshark-common
$ sudo usermod -a -G wireshark $USER
$ sudo reboot