Linux Security Overview and Understanding Firewalls

Network knowledge review

Overview of SELinux

SELinux working principle and working mode

Introduction to the security context of SELinux

SELinux user management

SELinux boolean operations

SELinux file context

SELinux process and port context

SELinux related troubleshooting process

Learn about small firewalls

Overview of iptables basics

The four tables and five links of iptables and the relationship between them

iptables workflow

Service installation and basic use of iptables

Detailed explanation of iptables management rule options

Detailed explanation of matching conditions of iptables

iptables firewall automatic configuration solution

Introduction to network firewalls

Prepare the NAT implementation environment

Experiment to allow the internal network to access the external network through SNAT

MASQUERADE performs address masquerading

Use DNAT target address translation to access the intranet server

Introduction to FireWalld and its features

Detailed explanation of FireWalld zone management

FireWalld installation and working principle

Configure using the firewall-config graphical tool

Introduction to area management of Firewall command firewall-cmd

Service management options for firewall-cmd

Utilize firewall policies to implement routing functions

Modify the firewalld configuration file to set up the firewall