How to Secure Your Linux VPS: 16 Essential Tips to Protect Your Virtual Server in 2025

Knowing how to secure your Linux Virtual Private Server (VPS) is crucial to prevent cyber threats. However, this isn’t a one-time task — in addition to following best security practices, you must continuously monitor your VPS.

In this article, we’ll dive deep into Linux security and its common vulnerabilities. We’ll also share 16 VPS security tips to help you prevent cyberattacks and keep your server safe.

Linux Security and Common Weaknesses

While Linux VPS security is generally strong, it does have a few weaknesses.Several types of cyber threats can compromise your server’s integrity and data. Here are the most common ones:

• Malware: Intrusive software designed to damage computers and their operating systems.

• Sniffing Attacks: Cyberattacks where hackers intercept and extract network data using packet sniffers.

• Brute-Force Attacks: A hacking method that uses trial and error to guess login credentials.

• SQL Injection: Occurs when an attacker exploits vulnerabilities in a web app’s code to access the database.

• Cross-Site Scripting (XSS): A client-side attack where malicious code is injected into a website.

• Broken Function-Level Access Control: When access rights aren’t properly verified, giving unauthorized users root-level privileges.

• Broken Authentication: Identity theft due to unencrypted data, weak passwords, or poorly configured session times.

Before applying security measures, monitor these key elements on your VPS:

• VPS hosting security

• Server software

• SSH connection

• Root access and logs

• Passwords and credentials

• Firewalls

• FTP connections

• User rights and privileges

• Server logs

  
  

16 VPS Security Tips to Protect Your Server

Below are 16 essential tips to safeguard your VPS from cyberattacks.

1. Check Your VPS Hosting Provider’s Security

Your VPS provider should have a solid security infrastructure and offer built-in protection. While you can always add extra layers of security, a good host comes preconfigured with key protections.

For instance, at HolyHosting, we apply advanced VPS security practices, including:

• Web Application Firewall (WAF) – filters and analyzes incoming requests.

• PHP Suhosin Hardening – strengthens PHP applications against common vulnerabilities.

• PHP open_basedir Protection – restricts PHP scripts to specific directories.

• BitNinja Server Protection – a full security suite for malware detection, IP reputation, and proactive defense.

• Advanced DDoS Mitigation – protection against distributed denial-of-service attacks.

• Monarx Anti-Malware – continuously scans your VPS for malware and suspicious activity.

• SSL Layer Security – encrypts data transmission between your website and visitors.

  
  

HolyHosting also offers automatic backups and live snapshots, making recovery easy after cyber incidents.For beginners, a managed VPS is ideal since the host handles updates, security, and malware scans automatically.

However, advanced users who want full control can opt for a self-managed VPS, gaining root access and technical support if needed.

2. Change the Default SSH Port

If your SSH connection still uses port 22, you’re an easy target. Hackers often scan open ports for brute-force attempts.

Change the default port to protect your data:

nano /etc/ssh/sshd_config

• Find the line Port 22

• Replace it with a new port number and remove the #

• Save and restart the service:

For Debian/Ubuntu:

service ssh restart

For CentOS/RHEL:

systemctl restart sshd.service

3. Disable Root Login

The root account has full control over your server — making it a prime target. Disable direct root login and use a regular user with sudo privileges instead.

Edit your SSH configuration:

nano /etc/ssh/sshd_config

Change:

PermitRootLogin no

Then restart SSH.

4. Use Strong Passwords

Avoid simple or personal passwords. Create long, complex ones with numbers and special characters.Use a password manager like NordPass to generate and store them safely.Change passwords every 3 months and never reuse them across multiple accounts.

5. Use SSH Keys Instead of Passwords

Passwords can be intercepted — SSH keys are much safer.They use cryptographic authentication and can be up to 4096 bits long.

Generate SSH keys:

ssh-keygen -t rsa

Press Enter through the prompts to create both public and private keys. Store the private key securely on your local machine.

6. Set Up an Internal Firewall (iptables)

Use Linux’s built-in iptables to filter incoming and outgoing traffic.

Install it on Ubuntu:

sudo apt-get install iptables
sudo iptables -L -v

7. Configure UFW (Uncomplicated Firewall)

UFW simplifies firewall management on Ubuntu:

sudo apt-get install ufw
sudo ufw enable
sudo ufw status

It blocks all incoming connections by default, reducing the risk of attacks.

8. Regularly Update Server Software

Always keep your OS and software up to date:

For Debian/Ubuntu:

sudo apt-get update && sudo apt-get upgrade

For CentOS/RHEL:

sudo yum update

Restart your server after updates.

9. Strengthen SSH Security

Disable password authentication and enable key-based authentication:

nano /etc/ssh/sshd_config

Set:

PasswordAuthentication no
PubkeyAuthentication yes

10. Restrict Access by IP

Limit access to your VPS to specific IPs:

AllowUsers username@IP

Replace username and IP accordingly.

11. Perform Regular Backups

Schedule automatic backups and store them off-site or in the cloud.HolyHosting provides built-in backup options through Panel.

12. Monitor Server Logs

Use logs like /var/log/auth.log and /var/log/syslog to track suspicious activity:

tail -f /var/log/auth.log

Set up alerts to detect unusual behavior early.

13. Install an SSL Certificate

Protect website traffic with SSL encryption — use free certificates from Let’s Encrypt.

14. Enable DDoS Protection

Mitigate denial-of-service attacks using DDoS protection tools.HolyHosting includes advanced DDoS protection in all VPS plans.

15. Use an Intrusion Detection System (IDS)

Install Snort or Suricata to detect malicious patterns and network anomalies. Review reports regularly and fine-tune detection rules.

16. Consult Security Experts

If you’re unsure how to implement certain measures, reach out to professionals. Security experts can audit your server and provide tailored recommendations.

Final Thoughts

Securing your VPS is an ongoing process that demands attention and consistency. Here are key takeaways:

• Stay Educated: Keep up with the latest cybersecurity trends.

• Be Proactive: Implement strong defenses before problems occur.

• Monitor Regularly: Watch logs and set alerts.

• Work with Experts: Their insights can greatly enhance your security.

• Act Fast: Have an incident response plan ready.

By following these 16 VPS security tips, you’ll significantly reduce vulnerabilities and strengthen your server’s defense against cyber threats.

Conclusion

We hope this guide has been helpful! 🚀 Remember, don’t hesitate to ask questions on the HolyHosting Discord or contact our support team.

Follow us on Twitter @HolyHosting to stay up to date.

Stuffy @ HolyHosting