I am a new user to the Asterisk world and i want to setup Astersik server for the call center .So plz help me in this regard .Thanks in advance.
What size is your call centre?
If you have a call centre, your phone system is key to your business, it would be best to purchase a supported Asterisk solution @ digium.com/
Follow this link for asterisk setup in your Ubuntu. Later you can go into config files, after asterisk is successfully installed and connected remotely.