Brief Introduction to Linux Firewall Configuration modification commands

The Linux Firewall Configuration Modification command is one of the most important commands in Linux. Here we will detail the instructions and specific steps for modifying the Linux firewall configuration.

To modify the firewall configuration, You need to modify the/etc/sysconfig/iptables file. If you want to open a port, add one in it.

-A RH-Firewall-1-INPUT-m state -- state NEW-m tcp-p tcp -- dport 1521-j ACCEPT

1521 indicates the port number to be opened, and then restart the Firewall Service in linux.

Command to stop/start the Firewall Service:

Run

Service iptables stop -- stop

Service iptables start -- start

(The service command is located in/sbin)

Firewall Rules can be activated only when the iptables service is running. To manually start the service, run the following command:

/Sbin rvice iptables restart

To ensure that it is started during system boot, run the following command:

/Sbin/chkconfig -- level 345 iptables on

The ipchains service cannot run with the iptables service at the same time. To disable the ipchains service, run the following command:

/Sbin/chkconfig -- level 345 ipchains off

In this way, the configuration of the Linux firewall is modified.

1. Linux Firewall Configuration Modification
2. Differences between Linux and Unix
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4. How to check Linux Security Vulnerabilities
5. Overall summary of changes in Linux shell output