Best 7 Ways to Secure SSH Server in Linux VPS

Securing your SSH (Secure Shell) server on a Linux Virtual Private Server (VPS) is of utmost importance to ensure the safety and integrity of your system. SSH is a standard tool used to access remote servers securely, making it a prime target for potential cyber threats. Implementing robust security measures can significantly reduce the risk of unauthorized access and potential security breaches. This guide will discuss the best seven ways to secure your SSH server on a Linux VPS. So, if security is your No. 1 concern, and you will buy Linux VPS, read or save it.

You must protect your VPS from new risks since eventually hackers will attempt to steal your data. Websites for businesses and organizations in particular are increasingly popular targets for hackers. Although most firms have some form of basic security in place, these measures are frequently ineffectual and readily broken.

1. Update Your SSH Software Regularly

Keeping your SSH software up-to-date ensures that you have the latest security patches and improvements. Use package managers like apt or yum to update SSH on your Linux VPS regularly. The panel you’re using, such as Plesk or cPanel, has to be updated as well. The majority of panels may be configured to update themselves automatically, and the majority of package updates in cPanel use EasyApache.

Additionally, you must concentrate on panels like Plesk or cPanel and examine notices if they are not automatically updated. Your operating system can be set up to deliver email notifications of yum package updates.

2. Change the Default SSH Port

Because they can’t find SSH, hackers have a difficult time breaking it. Malicious scripts won’t be able to connect directly to the default SSH port if the port number is changed. Change the default SSH port (usually 22) to a custom port to make it less predictable for potential attackers. Update the SSH configuration file (sshd_config) to reflect the new port.

To open ssh-config, run the command below and make the necessary adjustments:

/etc/ssh/sshd_config

Now, verify if any further services utilize the selected port number.

It’s crucial to understand that changing the default SSH port has no effect on your server’s security. It does, however, aid in preventing automated attacks.

3. Implement Key-Based Authentication

By utilizing a public/private key pair, key-based authentication replaces the “what you know” password element of the SSH authentication challenge. The user is specifically identified by this asymmetric encryption. More crucially, it does not call for manual password entry, at least in the case of automation. SSH automatically transmits the authentication key. In the event that the remote system accepts the key, authentication happens instantly and inaudibly.

To do this, you must utilize SSH key pairs for authentication instead of relying solely on passwords. Then, disable password-based authentication and only allow access via SSH keys. Finally, ensure that the private key is kept securely on your local machine.

4. Use SSH Configuration for Increased Security

Another method to Secure SSH server in Linux server, is to Modify SSH configurations to enhance security. The root client sign-in method should never be used. Because “root” is typically the username on Linux servers, hackers are attempting brute force attempts to guess the password and obtain access. Disabling root logins adds another degree of security by preventing attackers from figuring out the secret passwords. Instead of logging in as the root user, create a new username and use the sudo command to execute root-level instructions. Sudo grants authorized users’ special access that makes it possible to execute administrative commands without requesting root access. Make sure your non-root user is created and that the necessary level rights are offered before you disable the root account.

To do this, follow the below path:

•       Disable root login to prevent direct root access.
•       Limit SSH access to specific IP addresses using the AllowUsers directive.
•       Set login grace time and idle session timeout.

5. Utilize Two-Factor Authentication (2FA)

Make sure the password you use for your cloud accounts is strong, and abide by the minimum password implementation guideline. Never use the same password across many services; use a password manager; and create separate passwords for each. To preserve data and safeguard your account, enable at least two-factor authentication. Make sure you are informed if someone is attempting to reset your secret key, and if security issues are involved, make sure you ask probing questions.

6. Employ Firewall Rules

Your firewall is your first line of defense against hackers since it acts as the gatekeeper to the server, allowing or denying access. One of the initial steps when configuring a new Linux VPS should be installing and configuring a firewall. Instead of using the outdated and insecure File Transfer Protocol (FTP), use SFTP, which is “FTP over SSH.” You need a firewall on your VPS server to stop distributed denial of service (DDoS) attacks by filtering out superfluous traffic.

7. Monitor SSH Logs

Regularly monitor SSH logs to detect and respond to potential security threats. Tools like Fail2ban can automatically block IP addresses that show suspicious behavior. Also, you can use iptables to Restrict SSH Access.

Iptables is a Linux program used to monitor and filter incoming and outgoing server traffic as well as set up firewall rules. Almost all Linux distributions come with it by default. You may significantly increase the security of your server by using iptables to create rules that restrict or allow traffic for various services based on IP address, port, or network protocol. In our situation, we will configure the firewall to block all incoming SSH communication save for that from a single IP address or subnet. By doing so, blocking port 22 will not only prevent unwanted access to your servers but also mitigate or stop DDoS attacks. It’s important to watch out that you don’t totally block SSH traffic when performing this step-in order to prevent locking yourself out.

Conclusion

In this article, you learned How to Secure SSH server in Linux VPS. Web server infrastructure flaws can have disastrous effects. There are millions of hackers working around the clock to find even the smallest security holes in your Linux VPS. The suggested ways you reviewed can certainly increase your Linux VPS security.

Implementing these security measures will significantly enhance the security of your SSH server on a Linux VPS. It’s crucial to stay vigilant, keep software up-to-date, and regularly review and adjust security configurations to adapt to emerging threats. A well-secured SSH server is a critical component in maintaining a secure and reliable Linux VPS. Stay safe and keep your VPS protected!