Application requires IP address, need it to go to domain
We use a (poorly-designed) application that requires the IP address of our corporate office which has a static public IP address. However, when our failover internet kicks in, it obviously has a different static public IP address and then remote connections fail.
If the application would accept a domain name, I would use that with dynamic DNS, but it doesn't accept a domain name.
Is there any way to input an IP address but get to our domain name? I had two thoughts that I haven't tried yet.
Set up a local IP address that redirects to our domain name (e.g. 10.0.1.99 goes to local.ourdomain.com). However, I'm not quite sure how I would do this. Set up a Raspberry Pi with a web server maybe.
Purchase web hosting with a dedicated IP address and have it redirect to our domain which then could get updated as needed.
Any thoughts on how to achieve this?
A reverse proxy is a good idea, but may be limited by protocol.
I'd solve this problem by setting up a VPN (which provides security - if the app is that badly written it does not do a DNS lookup it's probably not using decent crypto either). Using a VPN means your addresses can all be rfc1918 ( ie private ones ), and the app won't even care when the external addresses change.