By "i have installed cfs" do you mean that you've installed CSF for ConfigServer Security & Firewall on the machine?
You likely need the cPanel, WHM and webmail ports to be opened:
cPanel ports - 2082 (non-secure) and 2083 (secure)
WHM ports - 2086 (non-secure) and 2087 (secure)
webmail ports - 2095 (non-secure) and 2096 (secure)
If you were only running iptables without CSF, you could run these commands to add those ports to iptables:
/sbin/iptables -I INPUT -p tcp -m tcp --dport 2082:2083 -j ACCEPT
/sbin/iptables -I INPUT -p tcp -m tcp --dport 2086:2087 -j ACCEPT
/sbin/iptables -I INPUT -p tcp -m tcp --dport 2095:2096 -j ACCEPT
After adding the ports, you would then save the configuration:
For CSF, you'd have to go into the Firewall configuration area and find the TCP_IN section, then add the ports there I believe.