How to Secure Your Dedicated Server: A Step-by-Step Guide

Dedicated Server Security HostingB2B is more important than ever in an age where data breaches and cyber threats are constantly evolving. Securing your dedicated server isn’t just good practice—it’s essential. Whether you’re handling sensitive customer data, meeting GDPR obligations, or aligning with ISO 27001 standards, a hardened server is your first line of defense.

This step-by-step guide from HostingB2B walks you through the essential layers of server security, from initial setup to ongoing protection and recovery.

Step 1: Initial OS Hardening Checklist

Before deploying any applications, you must harden your operating system. Here’s a quick checklist:

• Install only minimal packages (avoid GUI environments).
• Disable unused services and ports.
• Set strong passwords and enforce password complexity.
• Configure proper file permissions and user roles.
• Enable SELinux or AppArmor (depending on distro).
• Set up automatic log rotation and monitoring tools.

Pro Tip: Consider using hardened OS variants like AlmaLinux Minimal or Ubuntu Server.

Step 2: Configure a Firewall (UFW or iptables)

Your server should have strict traffic rules from day one. Use either:

• UFW (Uncomplicated Firewall) — ideal for beginners

sudo ufw default deny incoming 
sudo ufw default allow outgoing 
sudo ufw allow ssh 
sudo ufw enable

• iptables — more granular and powerful

iptables -P INPUT DROP 
iptables -P FORWARD DROP 
iptables -P OUTPUT ACCEPT 
iptables -A INPUT -m conntrack --ctstate ESTABLISHED,RELATED -j ACCEPT 
iptables -A INPUT -p tcp --dport 22 -j ACCEPT

Make sure your firewall rules persist across reboots using iptables-persistent or netfilter-persistent.

Step 3: SSH Hardening – Best Practices

SSH is a common attack vector. Secure it with the following best practices:

Disable root login:

In /etc/ssh/sshd_config

PermitRootLogin no

• Use SSH key authentication:

Disable password login:

PasswordAuthentication no

• Change the default SSH port:

Port 2222

• Restart the SSH service:

sudo systemctl restart sshd