Putting data in two separate forms at once

Putting data in two separate forms at once

I have an equipment form and an IP address form.  Currently I have it set up that to connect these two forms, I have a lookup field on the equipment form where you choose the IP address and on the IP address form there is a lookup field for the equipment ID.  However, that means I have to enter data in two places.  What I'd like to do is when I put in the equipment ID on the IP Address form that it automatically will put that information in the IP Address form and in turn puts whatever that IP address is into the equipment form.

Is there a way to do this so I'm not putting the information in twice?  Maybe a stateless form or something or perhaps an on success?