In many office types of environments, users are configured with a single public WAN and are NAT'ing (typically via a firewall or similar device) to servers LAN IPs.  To make this process simpler/easier, we added this capability into the Bacula4 Add Server Wizard

1) Check "NAT'ing behind an office firewall"

2) Enter in the WAN IP (every server at this location will have the same WAN IP in this scenario)

3) Enter in the LAN IP you are NAT'ing to

4) DO NOT use the default 9102 port, and instead, enter a custom port for each server you are NAT'ing to (we recommend you start with 9110 - so, server 1 will use port 9110, server 2 will use 9111, etc)

5) ensure you port forward requests appropriately at your firewall (ie server1 using port 9110 needs to have port 9110 forwarded to the associated server on your network)

We have also transposed this functionality to our BaaS module - as per below