SSH Hardening and Key-Based Authentication
Lock down the most exposed service on Linux servers: configure SSH for key-only login, disable risky defaults, and reduce the attack surface.
Why Harden SSH
SSH is the primary remote-administration channel and a constant target of automated brute-force attacks.
Hardening SSH dramatically reduces the risk of unauthorized access with a handful of configuration changes in /etc/ssh/sshd_config.
Generating a Strong Key Pair
Prefer modern Ed25519 keys over older RSA. Generate a pair with a passphrase for defense in depth.
ssh-keygen -t ed25519 -C 'admin@server'All lessons in this course
- Advanced Firewall Rules (nftables)
- VPN Concepts & Configuration
- Network Intrusion Detection (IDS)
- SSH Hardening and Key-Based Authentication