A Practical Linux Server Hardening Guide

Basic Steps

Before exposing a server to the internet, at minimum:

• Disable SSH login for root.
• Switch to key-based auth and disable passwords.
• Configure the firewall (ufw/nftables) to allow only the ports you need.
• Enable automatic security updates.

SSH Hardening

PermitRootLogin no
PasswordAuthentication no

Conclusion

Security is not a one-time task but a continuous process. Regular updates and monitoring are essential.