I am trying to allow a consultant access to my Debian Server and am a Linux newbie. I am unable to access the server from outside the network using SSH. I have two firewalls between the server and the outside. I have created an inbound service on the main firewall directed to the ip of the second firewall. Then on the second firewall I have allowed the ssh access to the internal ip of the server. Do I need to do something with NAT at the main firewall or do I need to configure the Linux Server to allow access from outside IP's?