📄️ IPTables
Iptables is a command-line firewall utility that uses policy chains to allow or block traffic. When a connection tries to establish itself on your system, iptables looks for a rule in its list to match it to. If it doesn’t find one, it resorts to the default action.
📄️ IPtables and getting locked out
Problem
📄️ Firewalld
Firewalld is a Linux management tool that provides a simpler alternative to the low-level and complex nftables, which replaced iptables in modern Linux kernels. It offers an easier way to manage firewall rules and configurations on Linux systems.
📄️ SSH-Based Logins
SSH key-based login is a method to securely connect to remote systems without using a password. Instead, it uses a pair of cryptographic keys: a private key, kept on your local machine, and a public key, placed on the remote server. This enhances security by eliminating the need for password-based authentication.
📄️ SELinux
The Need for SELinux
📄️ Security Updates
To check for high-priority, security updates, run the command below.