In today’s world, cloud-based servers have become essential to businesses. However, with the increasing reliance on cloud computing, cyber-attacks are becoming more frequent and sophisticated. In this article, we will discuss how to protect a cloud-based Linux server from various security threats.
Use Strong Passwords – The first step in securing a Linux server is to use strong passwords. This is the most basic and effective way to protect your server from unauthorized access. Passwords should be at least 12 characters long and include a mix of uppercase and lowercase letters, numbers, and symbols. You should also enforce password policies that require users to change their passwords regularly.
You could use LastPass & Password Generator online tools to generate stronger passwords.
Enable Firewall – Firewalls are a barrier between your server and the outside world. A properly configured firewall can help protect your server from various types of attacks. Linux servers come with built-in firewalls such as iptables and firewalld. You should configure your firewall to allow only necessary traffic and block all other traffic.
Cloud platform providers such as Amazon Web Services & DigitalOcean offers free firewall solution as part of their base offering.
Keep the Operating System Up-to-date – Keeping the operating system up-to-date is another essential step in securing your Linux server. Hackers often exploit vulnerabilities in software to gain access to a server. You should regularly update your software and operating system to the latest version to fix known vulnerabilities.
You can execute the following command within your Ubuntu/Debian-based Linux server to apply all the available operating system updates:
sudo apt update && sudo apt upgrade -y && sudo rebootNote: We recommend you take expert advice before applying the operating system updates. Sometimes, the applications deployed within your server may stop working after the update due to dependency deprecation, incompatibility with the newer software versions…etc.
Install Anti-Virus Software – Installing anti-virus software on your Linux server can help protect it from malware and other malicious software. ClamAV is a popular open-source anti-virus software for Linux. It scans your server for viruses and malware and quarantines any infected files.
Enable Two-Factor Authentication – Two-factor authentication (2FA) adds an extra layer of security to your Linux server. It requires users to enter a code or use a physical token in addition to their username and password. This makes it much harder for hackers to access your server even if they have your username and password.
Disable Root Login – Root login is the most powerful account on a Linux server, and it has unrestricted access to all files, directories, and system resources. Disabling root login can help reduce the attack surface of your server by removing a potential entry point for hackers.
Implement SSH Key Authentication – SSH key authentication is a more secure way to log in to your Linux server than a password. It uses public and private key pairs to authenticate users. The private key is kept on your local computer, and the public key is stored on the server. This makes it much harder for hackers to access your server by guessing your password.
Monitor Server Logs – Monitoring your server logs can help you detect and prevent security breaches. Logs record all activity on your server, including login attempts and file access. You should regularly review your logs to identify any suspicious activity.
You could use the below commandS to track the failed SSH login attempts within a Ubuntu based server:
grep "Invalid user" /var/log/auth.log
grep "Failed password" /var/log/auth.logConfigure fail2ban – Implementing fail2ban to protect your SSH login is a crucial security measure. One of the most common ways hackers attempt to gain access to a server is through brute-force attacks on SSH login credentials. Fail2ban can help protect your SSH login by detecting and blocking repeated login attempts from the same IP address. This can help prevent hackers from guessing your login credentials and gaining access to your server.
Fail2ban is easy to configure and can be customized to meet your specific security needs. You can configure it to block IPs after a specific number of failed login attempts, adjust the duration of the ban, and whitelist trusted IP addresses. This allows you to fine-tune your security settings to protect your server without inconveniencing legitimate users.
Securing a cloud-based Linux server requires a multi-layered approach. It would be best to use strong passwords, enable a firewall, keep your software updated, install anti-virus software, enable two-factor authentication, disable root login, implement SSH key authentication, monitor your server logs, and configure fail2ban. Following these best practices can help protect your server from various security threats and keep your data safe.
Need help with cloud server security? Contact the experts at Server Pundits for professional and reliable assistance.