.... or you can keep the same 8333 port on that computer and set up your router to forward a different port number on the router to port 8333 on the computer.
I am not sure that would work. A full node broadcasts the port it uses, so the node needs to know its global internet port. Having the router remap the port will mean that nobody will be able to connect to the 2nd node, since it will claim to use port 8333.
Besides these rules are usually 1st match, thus everything that comes in on port 8333 would be handled the same, regardless of a different later rule.
It appears that in order to run a full node port 8333 must be forwarded to that computer.
Not so.
Wouldn't it be nice if all problems were this easily solved.
To expand a little on this. You dont need to allow outside connections to run a full node. A full node that only uses the 8 outgoing connections that you get when you dont open and forward the port is still a full node.
The question I come up with is, why?
If node #1 is connected well to the internet, just let node #2 connect to node #1 locally. What is the benefit of you offering a service twice on the same IP? The nodes would compete for the bandwidth and unless the machines are very old would not max out alone anyway.
.... or you can keep the same 8333 port on that computer and set up your router to forward a different port number on the router to port 8333 on the computer.
I am not sure that would work. A full node broadcasts the port it uses, so the node needs to know its global internet port. Having the router remap the port will mean that nobody will be able to connect to the 2nd node, since it will claim to use port 8333.
Wouldn't it just not accept incoming connections?
If thats the result, why bother with a complex setup at all?