I we have run Ethernet in the house, through a fast Ethernet switch, through a wall patch, over the river and through the woods as it were. From router A, through switch, through wall patch, then to second router B. I read router to router, switch to switch, PC to PC, you want a crossover cable. I've wired one, but it only seems to work in one of the 1-4 slots on router B. How do we connect to router B internet slot? A patch cable? That would make some amount of sense, but I just wanted to verify that. To clarify, the run goes Router A -> Switch -> Wall Panel -> Router B #4. I would like for Router B to receive via its Internet port, but this does not seem to work with the crossover cable, hence supposing we just want a patch wiring there.


Most of the ports you'll find today have something called Auto MDI-X.

From https://en.wikipedia.org/wiki/Medium-dependent_interface:

"Auto MDI-X ports on newer network interfaces detect if the connection would require a crossover, and automatically chooses the MDI or MDI-X configuration to properly match the other end of the link."

You don't mention the model(s) of your devices so I can't lookup what you need exactly. Since both routers are (essentially) connected directly to your switch, I wouldn't expect you to need a crossover cable.

In addition all Gig ports have Auto MDI-X as it is part of the specification. You do, however, mention 'fast Ethernet' and that would signify a 100Mbit switch. Auto MDI-X on that is optional.

  • Router A is an ASUS RT-AC66U, connecting through a Netgear GS305, not sure specifics beyond that point, although pretty certain the switch is gigabit, through wall panel, to Cisco Linksys E1500. Currently crossover to the E1500 port 4. I've got the routers all configured to play nice together, that's not an issue. – Michael W. Powell Jan 12 at 15:37
  • Only one end of the connection needs to have Auto MDI-X. Since the Netgear GS305 is a Gigabit switch, you have that. I don't believe that there would be a need for a crossover cable in your configuration. If it isn't working as expected, I'd try all new patch cables. – toppledwagon Jan 12 at 22:38
  • I double checked today, it is a GS105, but it is the same underlying Auto MDI-X, if I understand correctly, called AutoUplink (TM) according to the Netgear specifications. – Michael W. Powell Jan 14 at 0:07

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