I have the following network situation.
I have 2 ISP supplied routers/modems at a location. I have device1-3 which has to be subnetted away from the router’s subnet and do not have to communicate with any of the other devices on the network. I have devices 4-6 which do not have to interact with devices 1-3. Devices 1&2 are connected to an unmanaged switch at one area and then a single cable runs to where the ISP modem/routers are located.
Device 3&4 are in another location away from where the ISP router/modem are located and are plugged into an unmanaged switch which has a single network cable run back to where the modems are located. This cable run is using shielded cable and was a bear to run and running another cable is iffy.
Devices 5&6 are on their own separate network cables which run up to the ISP cable modems. I had thought of adding the "router (dd-wrt) " by the ISP modem/touters to subnet off device 4-6. The problem is that this will isolate device 3 which needs to communicate with the network printer.
Any ideas how I can subnet off device 4-6 and have device 3 on the same subnet of device 1&2 and the network printer?