Mac-Mini: Three Ethernet Ports, or do I?

I have read a couple threads on other sites, but nothing is working for me.



This is what I need to do.



One of the responsibilities of my job is to maintain my companies owners network in his home. It is small, no big deal at all. The network is set up as follows:



2 T-1 Lines (1 UP, 1 DOWN) connected to a cisco border router. The border router is connected to a switch. Excluding the network IP and gateway IP, there are 5 available IP address. I have two seperate routers connected to the switch (and video server, but that isn't involved) that each create two seperate subnets. The reason for this is A for backup, if router A goes down for some reason, he can just connect to router B. Also because one router serves his computers and the other his wifes. While there might be a better way to set this up, this is what I need, it does what I want, and complies with other needs that I did not list.



The problem, I live 3 hours away and rarely get back there. Recently I had to go back to fix a problem, that was not fun. There is no one at his house that is knowledgable enough to anything with this, so involving them is not an option.



I have a Mac Mini that I want to connect to 1) The border router (given a public IP address) 2) Router A and 3) Router B. Sometimes there are power problems there and the backup batteries don't last long enough and for some reason every once in a while the setting get erased and restored to the default.



My plan is to remotely connect to the mac mini with apple remote desktop (which I already had licenses for anyway), switch to the network interface of the router having the problems (obviously A or and reconfigure it. Another key reason is the remote control of the computer on the network, I want to make this mac mini the other outside entry point to the network, make it very secure and then just access local VNC ports. If the Cisco router goes down, I can can call into a modem connected to it and fix it, so the mac mini will always have an internet connection, even if router A or B goes down.



I assume the best way to do this is to connect two additional network cards and plug them in seperately and switch the interface as needed. If there is a better way where all the above conditions are met, please let me know.



I have download the pegasusUSB drivers and the USB2 one (whatever they are called) and I still have no luck. The adapter show up as being connected in the system profiler, but when I go to network prefs, no new port is detected. I have tried three different adapter (all of which are supposed to be supported under pegasus) and no luck with any. On one the link/act light come on, but on the other there is nothing.



Any help would be greatly appreciated.



Thanks, Justin.