Hi Peter, thank you for using our forum, my name is Luis I am part of the Small business Support community. I am more that glad to assist you with your configuration please follow these steps.
Step 1. Go to Setup > Forwarding
Step 2. You could select your service or add the service in service management.
Note: If you need to add the service you need to:
- Set Service Management name.
- Select TCP or UDP.
- Select the Port Range; in your case you could use 22 in both.
- Select Add, then select the protocol that you create and double click on it.
Step 3. In the IP Address field, enter the LAN IP address.
Step 4. Click on Enable.
Step 5. Click on Add New.
Step 6. Save your changes.
I hope you find this answer useful
Greetings,
Luis Arias.
Cisco Network Support Engineer.