I recently posted a few ideas on the opportunities for web developers in Facebook.

I decided to use DynDNS for creating a host name for my local DSL connected Ubuntu box, it's easier editing and making changes that way instead of using the other servers I have in a couple of data centers. I used the hostname as a callback url for a Facebook test application. Facebook saw my host and the application worked as expected.

A couple of hours later I disconnected from the Net to take a break, when I got back received a new IP address from my ISP's DHCP server and DynDNS updated my host information to point to the new IP. Unfortunately now Facebook can't find my callback url anymore. I tried editing settings and changed the host name to the new public IP address to discard, still no luck and I'm getting this error:

The URL http://xx.xx.xx.xx/facebook/application-name/ did not respond.

There are still a few kinks Facebook and the makers of application-name are trying to iron out. We appreciate your patience as we try to fix these issues. Your problem has been logged - if it persists, please come back in a few days. Thanks!

Is Facebook caching my older IP address? That was my first thought but even putting the actual public IP of my box in the callback url didn't work.

Is this a temporal glitch in the Facebook Platform or am I missing something else?

I'll keep testing but if you have any ideas I'd love to know.

Fixed: I'm an idiot! I forgot changing the IP address of my database server, also in my local box. Now everything's working again.