You should be looking for the service named or bind, which is the DNS server on Linux systems.
First, make sure it is running, otherwise, try to run it (and find out why it's not starting up by itself) from the starting scripts folder /etc/init.d/. Here, you should have a starting script called bind or bind9 or named. Try to run it and make sure that it is started (check if the port is open netstat -an | grep 53).
