Hi, I would like to tap into the well of knowledge that is in this community.
My girlfriend and I play Rainbow six siege together, but we have been having some connections issues lately. Nat type was moderate but once I forwarded the necessary ports to my computer it is now open. However I can only forward the ports to one IP address, so on my girlfriends machine it still says moderate. How do I solve this?
My router is a Linksys EA6900 it's in the first floor of our house, I have also connected it to a ASUS RT12, which is located on the second floor, through Ethernet to extend the WIFI (only 2,4ghz). My machine is currently on WIFI (2,4ghz)and my girlfriends is cabled. The Asus router is setup as an access point.
We can play for extended periods without trouble but would still like to have open Nat type on both machines.
First you have to understand what NAT does. NAT stands for network address translation that basically translates your private IP addresses inside your home (usually something like 192.168.x.x) into a publicly route-able set of IP addresses. In consumer routers this is usually only used to "masquerade" your internal computers behind one single public IP address. This not only functions as sort of a simple firewall but also saves public IP addresses, that in the case of IPv4 are exhausted.
Now this masquerading aspect of the NAT is your problem in this situation. A machine on the internet can't access a machine on your home network directly, since that machine doesn't have its own address on the internet (all your devices share one IP address). This means that if a packet reaches your router from the internet, it doesn't know where it needs to be forwarded to and will simply drop it.
By setting up port forwarding rules, you tell your router to forward packets for a specific port to a specific device in your home network. Now if you want to use the same set of ports for two machines (at the same time), this will not work, because both type of packets (the one intended for your computer and the one for your girlfriend's one) will look the same to your router (both have the same destination port). If you could tell the game's server to use different ports for both of your computers, this would work again.
To solve your problem, all you can do is to get more public IP addresses. Since your ISP will most likely not give you more than one IPv4 address, your only option really is to use IPv6. If your ISP provides you with a IPv6 subnet or you get your own IPv6 subnet through an IPv6 tunnel, you can make both machines accessible from the internet. However, this will only work through IPv6, so if your game's server doesn't support IPv6, you're out of luck.