Hello everyone. Let me start by saying that I am new to Raspberry Pi's, but have some experience with Linux Ubuntu.
I am working on a project to improve some network training I conduct. Being aviation related, there's no way I can get approval to buy the actual aircraft parts, so I'm trying to use RasPi's (running Raspian Buster) to simulate/emulate the actual components.
I have html based emulators for maintenance GUI's for some systems. I already managed to set up a Pi with Apache and host one of these emulators. With a computer on a 10.x.x.x network, I can access it through the router's WAN port at 172.29.55.x as it's set up on the aircraft.
What I would ultimately like to do, is take this current Pi, and set a second ethernet interface with the same IP. The component I'm mimicking has a secondary "maintenance" port that allows access to the GUI, but only for a computer with a static IP of 172.29.55.x. I understand the USB ports are connected to the LAN interface and a USB to RJ45 adapter should work.
So, here's what I can't figure out how to do.
Eth0 - static IP of 172.29.55.1/24, connected using the RJ45 port to the WAN port of my training network (currently functioning, can be accessed from the 10.x.x.x network)
Eth1 - static IP of 172.29.55.1/24, connected to via USB to Ethernet adapter but only by a computer set to 172.29.55.10 (what I'm adding)
If possible, it would be nice to add another USB to Ethernet adapter (eth2) to connect another Pi (different IP address) that would allow clients to ping the second Pi from my 10.x.x.x network; however I am not opposed to purchasing an ethernet switch.
I have tried adding an eth1 interface in by editing /etc/dhcpcd.conf and /etc/networks/interface, but probably not correctly.
If anyone can help me, I'd be very appreciative.