The function of selinux and the method of centos7 to close selinux

SELinux, fully named Security Enhanced Linux, is a mandatory access control mechanism based on the Linux kernel. It can effectively improve the security of the system by marking system resources and processes, matching rules and other operations. Generally, our server will be shut down. Although it has certain firewall capabilities, it is generally not used as a firewall setting.

The main functions of SELinux are as follows:

1. Provide stronger access control: SELinux can perform fine-grained access control on all system resources and processes, including files, network ports, IPC, etc., thus improving the security of the system.

2. Prevent unauthorized operations: SELinux can prevent unauthorized processes or users from accessing or modifying sensitive resources.

3. Reduce security vulnerabilities: SELinux can limit the access rights of applications while they are running, thus reducing the security risks caused by application vulnerabilities.

The method to turn off SELinux is as follows:

4. Temporary shutdown: You can use the following command to temporarily shut down SELinux:

 setenforce 0

This command can only take effect in the current session. The default settings will be restored after restart.

2. Permanent shutdown: If you need to permanently shut down SELinux, you need to modify the configuration file/etc/selinux/config, change the value of SELINUX to disabled, and then restart the computer.

 # This file controls the state of SELinux on the system. # SELINUX= can take one of these three values: #     enforcing - SELinux security policy is enforced. #     permissive - SELinux prints warnings instead of enforcing. #     disabled - No SELinux policy is loaded. SELINUX=disabled # SELINUXTYPE= can take one of these two values: #     targeted - Targeted processes are protected, #     mls - Multi Level Security protection. SELINUXTYPE=targeted

After modification, restart the computer with the following command:

 reboot

It should be noted that although SELinux can reduce the security of the system, it may cause the application to fail to run normally under certain circumstances. Therefore, relevant risks and impacts should be evaluated before shutdown. Generally, we close and use other firewalls to configure server security.