Creating Multiple IP Addresses On Port

Hi i’m working on a project that involves our RPI 3 connecting to multiple networks over ethernet. One network would be a DHCP enabled connection to the internet. The other network would typically not have a router and would want a static IP address. This does mean the RPI 3 is plugged into a switch.

I had noticed on older builds of resin (~2.0.X, its been a while) that we had multiple IP addresses assigned to us through errors in my configuration file / plugging in my device. The thing is now I want to do it on purpose, and can’t seem to make it work!

I’ve poked around the forums enough to know that there are such things as “Phantom” Ip addresses (Phantom IP Addresses), so it may be that what I noticed was not even reality.

I have a few questions:

  1. Is it possible to assign two IP addresses to the sole ethernet port on the RPI 3?
  2. If so what is wrong with the files that I have attached (In my image they are not .log files, just added that so that I could upload them).
  3. I know DHCP is enabled by default. Is there a way that I could plug in a fresh device, stop it, add a config file, then re-attach it to get multiple networks?

resin-eth 2.log (118 Bytes)
resin-eth 1.log (147 Bytes)

We are currently looking at adding an external HW solution, but thats is not ideal.

Any help that could be provided would be great, thank you.