Linux Server Security Hardening

Security should never be an afterthought. Whether you manage a cloud server, VPS, dedicated server or enterprise platform, implementing security best practices can dramatically reduce the risk of compromise, malware infections and unauthorized access.

Security Hardening Checklist

✓ System Updates

✓ SSH Hardening

✓ Firewall Configuration

✓ Fail2Ban Protection

✓ Malware Scanning

✓ User Management

✓ Security Monitoring

✓ Backup Strategy

Keep Your Server Updated

Security updates fix vulnerabilities that attackers actively exploit.

sudo apt update
sudo apt upgrade -y
sudo apt autoremove -y

SSH Hardening

SSH is the primary target for automated attacks.

sudo nano /etc/ssh/sshd_config

PermitRootLogin no
PasswordAuthentication no
PubkeyAuthentication yes
MaxAuthTries 3

sudo systemctl restart ssh

Configure UFW Firewall

sudo ufw allow OpenSSH
sudo ufw allow 80
sudo ufw allow 443
sudo ufw enable

sudo ufw status verbose

Install Fail2Ban

sudo apt install fail2ban -y

sudo systemctl enable fail2ban
sudo systemctl start fail2ban

sudo fail2ban-client status

Secure User Accounts

sudo adduser cloudadmin

sudo usermod -aG sudo cloudadmin

sudo passwd -l unwanteduser

Install Malware Scanner

sudo apt install clamav clamav-daemon -y

sudo freshclam

clamscan -r /home

Secure File Permissions

find /var/www -type d -exec chmod 755 {} \;

find /var/www -type f -exec chmod 644 {} \;

Disable Unused Services

sudo systemctl list-unit-files --type=service

sudo systemctl disable service-name

Monitor Active Connections

ss -tulpn

netstat -tulpn

lsof -i

Security Monitoring Tools

✓ Fail2Ban
✓ ClamAV
✓ ImunifyAV
✓ Wazuh
✓ OSSEC
✓ Zabbix
✓ Prometheus

Backup Strategy

✓ Daily Backups
✓ Offsite Storage
✓ Automated Verification
✓ Disaster Recovery Testing
✓ Multiple Retention Policies

CloudRevol Security Stack

CloudRevol secures Linux servers using a multi-layered security approach designed to protect websites, applications and cloud infrastructure.

🛡 Firewall Protection

🔍 Security Monitoring

🚫 Malware Protection

⚡ Proactive Patching

💾 Automated Backups

🚨 Intrusion Detection