Run system updates immediately upon setup (e.g., apt update && apt upgrade for Debian/Ubuntu or dnf update for RHEL/Fedora).
Moving SSH from port 22 to a non-standard port can eliminate up to 99% of automated scans. 3. Identity and Access Management Linux Server Hardening
Disable password-based authentication ( PasswordAuthentication no ) in favor of SSH key-pair authentication . Run system updates immediately upon setup (e
The most critical step is ensuring all software is current to close known vulnerabilities. Linux Server Hardening
Prevent direct root access by setting PermitRootLogin no in /etc/ssh/sshd_config .
Configure automatic security updates using tools like unattended-upgrades on Debian/Ubuntu or dnf-automatic on RHEL/Fedora. 2. Secure Access (SSH Hardening)
Securing the primary remote entry point is vital for stopping automated brute-force attacks.