As a young adult, you may be responsible for managing your own Linux servers, or at least be interested in learning how to keep them secure.
The truth is, even if you have a limited understanding of Linux, you can still take steps to protect your servers from cyber attacks.
In this guide, I’ll be sharing my top 10 Linux server security tips to help you keep your data safe and secure.
1. Provide the necessary
Creating a strong password and enabling two-factor authentication are the first steps to securing any system. The password must be at least ten characters long , including special characters and letters (lower or upper case). Use different passwords for different users or software systems. Change your password within a certain period of time, as no password can provide adequate protection indefinitely.
Several password managers are available for password protection and synchronization , such as BitWarden, LastPass, Enpass, Dashlane, and others. However, a single password manager is ideal for every server. Therefore, it is very important to choose the right one according to your requirements.
2FA offers an extra layer of security and immediately removes the risk of password compromise. You can use 2FA with secure shell (SSH) to enforce second credential requirements during the login phase. Thus, 2FA and a strong password can increase resistance to brute-force attacks and unauthorized logins, as well as improve server security.
2. Generate an SSH Key Pair
Passwords can help, but there are other ways to log into private servers that are significantly more secure. It is recommended that you use Secure Shell (SSH) key pairs for deployment because they make brute-force attacks more difficult.
Before using them, it’s important to understand why you might want to use SSH keys instead of the traditional username and password setup. While passwords are more convenient for familiar users, those same people often rely on easy-to-guess options, putting the entire security infrastructure at risk.
SSH key pairs are significantly more secure than passwords, but less user-friendly . This security improvement may be due to the encryption used by both the server and the computer. Simply put, an SSH key pair is equivalent to a 12-character password. Therefore, when implementing a proactive server security policy, make sure you use SSH key pairs.
3. Keep your system up to date
To keep your Linux server safe and secure, make sure to check for new updates. To address security holes, new patches may be released. Many Linux users have difficulty installing these patches. This can make the server vulnerable to hacking. If you are having difficulty updating security updates, automate the process.
Automatic updates can be turned on to ensure that everything is up-to-date. Automatic updates can sometimes download unneeded fixes. Please review the updates before you release a new update. Regular updates are important in order to prevent security breaches and unauthorized access.
You should also update your content management system, plugins and other advanced features as every patch fixes security issues.
4. Remove any unnecessary software
Although installing new software can be attractive, not all online services will be necessary.
To expand functionality, you can add other packages. Once you have installed any package, it will be able to access your server. The vulnerability of your server can be increased by installing additional software and packages. You must get rid of all unnecessary software and packages to protect your Linux server.
The lack of the right tools can result in serious security problems over time. At least once per year, conduct a system-wide cybersecurity and software audit. This simple commitment will improve your server’s performance and help you keep it running efficiently even when new applications are installed. To view the most recent items, you can use Red Hat Package Manager (RPM).
5. Close all ports
An attacker can use open ports to gain access to network architecture information, which increases attack possibilities. These vulnerabilities can be used by attackers to gain access the server. Block all unused ports to stop new services binding to them.
It is better to locate open ports and close them as quickly as possible. Netstat commands can be used to list all incoming connections. To protect your server, you should immediately close any port that is open.
6. Disable downloading from an external device
External devices, such as USB drives, can be used by attackers to gain access to sensitive information.
Physical attacks can be reduced by disabling booting from external devices. This can also reduce the risk of hacking. Without this additional step, anyone can bypass many layers security. To keep your server secure, make sure to disable booting from external devices.
7. It is vital to conduct a security audit
Although the above tips can make your server more secure, there are always new threats. If your server isn’t updated correctly, even the most secure servers can be vulnerable to new threats. Software updates are essential, but a security audit might uncover other helpful improvements.
It can be difficult to identify the weaknesses and fix them so your server is secure. To avoid any security problems on your Linux server, you need to conduct regular security audits.
8. Regular backups should be created and maintained
To ensure security, backups are vital. Backups are essential to restore data in the event of a server intrusion. The Linux version of the Rsync program is popular for data backup. You can create daily backups and avoid duplicates of certain files with its many options.
It’s well-known for its versatility. This makes it an excellent choice to use for a variety of Linux server security strategies. Backups are more effective if they are regularly tested. You can ensure that backups are accurate and contain the most recent files, and that they can be restored quickly in the event of data loss.
9. Turn on the firewall
A firewall can protect the system from unauthorized access.
Hence, it is useful to check the firewall to ensure the security of the server. iptables offer a fantastic way to filter all outgoing, incoming, and forwarding IP packets.
You can create allow and deny rules to receive or send traffic from a specific IP address . These rules restrict unauthorized traffic or any movement on the server.
Nowadays, DDoS (Distributed Denial of Service) attacks are becoming commonplace and can pose a threat to the server. This is why enabling a firewall can protect your system from DDoS attacks.
10. Use SELinux
SELinux, also known Security-enhanced Linux, is a great security architecture for Linux. This allows the server administrator access and control the system. SELinux employs a variety of security policies to determine the reachable and reachable servers.
SELinux checks a user’s access to a file (object) by using AVC (Access Vector Cache). This cache stores all permissions for both the subject and object. It is therefore useful to implement SELinux to protect your Linux server against any third-party attacks.
SELinux can be used in two modes: permissive and enforcement. Enforcement is an enhanced security mode which enforces all policies to improve security. Permissive mode in SELinux doesn’t enforce server policy, but logs and validates the actions.
Linux Server Security is always important
It is worth the extra effort to protect your Linux server. Remember that Linux and server protection are an ongoing process and requires regular checks, software updates, and data backups. These requirements will save you a lot.
Spend time learning basic security procedures and developing a stronger password strategy. You will have a stronger server that can withstand some of the most serious security threats.
So do not forget this tips:
- Keep the operating system and applications up to date: Regularly apply security updates to the operating system and all installed applications.
- Use strong passwords: Use long, unique passwords for all user accounts, and consider using a password manager to store them securely.
- Enable two-factor authentication: Use two-factor authentication (2FA) to add an extra layer of security to user accounts.
- Configure firewalls: Use a firewall to restrict incoming and outgoing traffic on the server.
- Enable SSH key-based authentication: Use SSH key-based authentication instead of passwords for secure remote access to the server.
- Harden network services: Configure network services such as FTP, SSH, and HTTP to use secure protocols and remove any unnecessary services.
- Monitor logs: Regularly monitor system logs for unusual activity and investigate any suspicious entries.
- Restrict access: Limit access to the server to only authorized users and groups, and use secure protocols such as SFTP or FTPS for file transfers.
- Use encryption: Encrypt sensitive data such as passwords and SSL keys to protect them from unauthorized access.
- Implement physical security: Protect the physical server and ensure that only authorized personnel have access to it.
