iptables open port

iptables open port 

IPTables, a linux utility enable to control port access in a System.

To Open a port via iptables,



iptables -A INPUT -p udp --dport 161 -j ACCEPT

iptables -A INPUT -p tcp --dport 161 -j ACCEPT

where ,

-A stands for append a rule
-p stands for type of port ( TCP / UDP )
-dport stands for destination port number


Refer: http://wiki.centos.org/HowTos/Network/IPTables