I want to change to web server port from 80 to 8080 (coz my ISP blocked to port 80). I then go to /etc/apache2/ and tried to modify the httpd.conf file by Text Editor. But I found that I can't save any change and an error meesage like "You have no privilage to save the file" always appear.
First of all, am I modifying the right file? Secondly, how can I save the changes?