I have a basic Apache server running behind my VPN, which forwards the necessary ports and assigns a DDNS name to the exit IP. It works initially, and I'm able to use the name to access my apache server -- for awhile. Sooner or later, the exit IP changes but my DDNS does not automatically update like it (presumably) should. I ran a DDNS report, and all the DNS servers are pointing to a now defunct address. The only way I can update it is to re-do the port forwarding rule with the name assignment. Server-side is nothing special. It automatically connects using an OpenVPN config file, but is otherwise untouched.
How do I trigger a DDNS name update without having to re-do my port forwarding and name assignments every time? Do I need to configure my OpenVPN files to trigger DDNS updates?