ptablesSecuring Linux System with SSH and IPTables（linuxsshi）
Linux is an open source server operating system that is widely used due to its stability and reliability. Although Linux is one of the most secure operating systems around, it is still vulnerable to cyber attacks and malicious activities if left unprotected. Before you deploy any Linux system, it is important to ensure that it is safe and secure from unauthorized access and potential threats.
In order to secure the Linux OS, you must use the built-in security features such as SSH and IPTables. SSH (Secure Shell) is a protocol for secure communication over an unsecured network. SSH allows you to safely log into a remote machine and execute commands. It encrypts all communication between the client and server, making it impossible for an attacker to intercept the communication.
IPTables is a firewall application designed to protect the Linux system from attacks or other unwanted access. It is configured with a set of rules to filter incoming and outgoing traffic. For example, you can use IPTables to block certain IP addresses or ports. You can also use it to allow or deny specific services or applications.
Apart from using SSH and IPTables, there are several other measures you can take to further secure your Linux system. As a precautionary measure, always install the latest security patches and security updates. You can also use third-party tools or services like antivirus protection and a web application firewall to extend your security perimeter. Additionally, create strong passwords and use other authentication methods such as multi-factor authentication to reduce the risk of unauthorized access.
To set up SSH and IPTables, first you need to install them on your Linux system. IPTables can be installed with the command
`sudo apt-get install iptables`.
Once installed, you can configure the rules to suit your needs. You can add rules using the `iptables`command in the following format:
` iptables -A INPUT -p tcp -s –dport -j DROP `
Similarly, you can setup SSH by enabling the SSH server as a service. You can do this by typing the following command in the terminal:
` sudo systemctl enable sshd.service `
Once enabled, you’ll need to create an SSH key pair for authentication. You can do this with the following command:
` ssh-keygen -t rsa -b 4096 -C ‘email@example.com’ `
Once the SSH key pair is generated, you can add the public key to the authorized_keys file in the .ssh folder of the remote machine.
By using SSH and IPTables, you can successfully secure your Linux system and protect it from malicious attacks and unauthorized access. There are several other security measures you can implement to further fortify your system, but SSH and IPTables are the two most important tools for locking down your Linux system.
