The standard SSH port 22 is a popular target for attackers. If you want to additionally secure your Raspberry Pi, you can simply change the port for SSH access. In this guide, I will show you step by step how to do this.
1. Select a free port
Before you get started, you should think about which port you want to use in the future. This is important:
No port duplication! A port already used by another service leads to conflicts.
Wikipedia can help: You can find an overview of known and reserved ports on Wikipedia.
Tip: It is best to choose a port between 1025 and 65535 that is not used elsewhere, e.g. 1357.
2. Edit SSH configuration file
Open a terminal and edit the sshd_config file, which contains the SSH server settings:
sudo nano /etc/ssh/sshd_config
3. Find and change the port line
Search for the Port entry in the file using the key combination CTRL + W. You will probably find the following (commented out) line:
#Port 22
Remove the # and replace 22 with your desired port:
Port 1357
4. Save file and close editor
Save:
CTRL+O, then EnterExit:
CTRL+X
5. Restart the SSH service
The SSH service must be restarted for the change to take effect:
sudo systemctl restart ssh
6. Test connection
If everything went well, you can now connect via the new port – enter the new port after -p:
ssh pi@your-ip-address -p 1357
…or:
ssh allsky.local -p 1357
Conclusion
With just a few simple steps, your Raspberry Pi is a little bit more secure. Of course, changing the default port does not replace other important security measures such as public key authentication or Fail2Ban – but it is a sensible first step.