Enable iptables firewall for CentOS and iptables for centos

Enable iptables firewall for CentOS and iptables for centos

In fact, these things should be clearly written as soon as they are completed. They have been written for a long time. Maybe they have not been written in some places. I hope to see the kids shoes for help and I will update them again, if any error occurs, please criticize and correct it.

I used iptables as a firewall before 7.0 and firewall after 7.0. I don't know why, but most people use iptables, so I also use it.

1. Disable firewall

1 // stop firewall2 sudo systemctl stop firewalld. service3 // disable firewall startup 4 sudo systemctl disable firewalld. serviceView Code

2. Install the iptables firewall.

1. Install

1 // install 2 sudo yum install iptables-servicesView Code

2. Configuration

1 // edit iptables, use sudo 2 vi/etc/sysconfig/iptables 3 // file content 4 # Firewall configuration written by system-config-firewall 5 # Manual customization of this file is not recommended. 6 * filter 7: input accept [0: 0] 8: forward accept [0: 0] 9: output accept [0: 0] 10-a input-m state -- state ESTABLISHED, RELATED-j ACCEPT11-a input-p icmp-j ACCEPT12-a input-I lo-j ACCEPT13-A INPUT-m state -- State NEW-m tcp-p tcp -- dport 22-j ACCEPT14-a input-m state -- state NEW-m tcp-p tcp -- dport 80-j ACCEPT15-a input- j REJECT -- reject-with icmp-host-prohibited16-a forward-j REJECT -- reject-with icmp-host-prohibited17 COMMIT18 // save file 19 C + C and then: wq exit-> due to the habit of emacs, the C here represents Ctrl, And so C + C is actually Ctrl + C, which will be easy to write in the future. 20 // restart the firewall to make the configuration take effect 21 sudo systemctl restart iptables. service22 // set the firewall to start up 23 sudo systemctl enable iptables. serviceView Code

OK. Now, your iptables has been configured. If you want to add a port later, proceed to the next step.

3. open ports

1 // replace * with the port number you want to open 2/sbin/iptables-I INPUT-p tcp -- dport *-j ACCEPT3 // Save the configuration 4/etc/rc. d/init. d/iptables save5 // view the changed iptables6/etc/init. d/iptables status7 // restart iptables8 sudo service iptables restartView Code

Well, these are some basic configurations related to iptables. I hope you can tell me something that is difficult.

Reprinted please note
Author: Spring of Li xiao'er
Address: http://www.cnblogs.com/LittleTwoLee/p/5048771.html