Which port is SSH?

The default port for SSH (Secure Shell) is 22.

Understanding SSH and Port 22

SSH is a cryptographic network protocol that enables secure data communication, remote command-line login, and other secure network services between two networked computers. It is fundamental for managing servers and connecting to remote devices securely.

Key Aspects of SSH Port 22

Default Port: The standard port number assigned to SSH is 22. This is widely adopted and well-known across operating systems and network devices.
IANA Assignment: The Internet Assigned Numbers Authority (IANA) officially registers port 22 for SSH.
Security Implications: While port 22 is the default, it's also commonly scanned by malicious actors. Therefore, it is crucial to implement robust security measures when using SSH.

Why Port 22 is Important

The selection of port 22 for SSH is not arbitrary. It's a convention that allows network administrators and users to quickly identify the traffic associated with SSH connections. This facilitates straightforward setup, troubleshooting, and management of network services.

Changing the SSH Port

While port 22 is the default, you have the option to change it to enhance security. By using a non-standard port, you can reduce the risk of automated attacks.

Steps to Change SSH Port (General Guidance)

Locate the SSH Configuration File: Typically, this file is named sshd_config and is found in the /etc/ssh/ directory.
Modify the Port Directive: Find the line that reads Port 22 and change 22 to your preferred port number. Example: Port 2222.
Restart the SSH Service: Apply the changes by restarting the SSH service. The specific command may vary depending on your operating system (e.g., sudo systemctl restart sshd or sudo service ssh restart).
Update Firewall Rules: If a firewall is active, ensure that you update it to allow connections through the new port.

Summary

In short, while the default SSH port is 22, being aware of its purpose and the security considerations is crucial. Remember, while changing the default port can enhance security, it’s essential to maintain a robust overall security posture.