To block outgoing traffic to a port, (e.g.

Iptables -A INPUT -d 192.168.1.100 -p tcp -m tcp -dport 21 -j DROPīlock an IP address (e.g. 192.168.1.111) and block access from all other IPs to the server (e.g. Iptables -A INPUT -p tcp -dport 443 -j ACCEPTĪllow access on port 21 from a specific IP address only (e.g. Listed below are examples about common firewall rules.Īccept all ESTABLISHED and RELATED packets: iptables -A INPUT -m state -state ESTABLISHED,RELATED -j ACCEPTĪllow HTTP and HTTPS connections from anywhere: iptables -A INPUT -p tcp -dport 80 -j ACCEPT Now, Lets see the common firewall rules in iptables That’s it, now you should have successfully installed iptables on your server. If there is CentOS installed on your VPS, run the following commands: yum clean all If you have an Ubuntu VPS or a Debian VPS, run the following commands: apt-get updateĪpt-get install iptables iptables-persistent Log in to your VPS via SSH as user root ssh -p Port_number ssh -p 22 Let’s get started with some common firewall rules and commands in iptables. A chain is a list of firewall rules which are followed in order.

Iptables contains five tables: raw, filter, nat, mangle and security. Iptables is a useful command line utility for configuring Linux kernel firewall. Here we are going to show you some linux common firewall rules and commands in iptables. Linux Common Firewall Rules and Commands in iptablesĪ firewall is a network security device that monitors incoming and outgoing network traffic and decides whether to allow or block specific traffic based on a defined set of security rules.

Iptables command in linux