> Is there some way I can redirect a request to 10.100.1.5 over to 10.205.3.7?
No not in DNS, for a start an IP based request wouldn't touch DNS. But even if it did, DNS doesn't redirect.
> I am guessing I will need to do some sort of "ARP poisoning" to get this to work...
I'm not even going there, it's not a good path to walk.
> Is there some way I can redirect a request to 10.100.1.5 over to 10.205.3.7?
It depends entirely on the service, but the most likely answer is no, especailly considering the implied change in IP address range. Will a client be able to route to the old IP? Will you be able to set something up to answer on the old IP?
Your best bet is to find and fix things using IP addresses, make them use a name. It's not a pleasant or quick solution, but it is the correct solution.
Chris
