I have some devices that are only accessible via RS-232 cables. The problem is that I have no RS-232 to USB adapters so I can't access them.

What I do have is a bunch of serial cables, most interestingly Cisco RJ45 (8P8C) to RJ45, that happen to fit in ethernet ports.

I've found this article that points out that you can use socat (installable via Homebrew) to open a PTY to work with serial over Ethernet, but it doesn't go into any detail on how that would work.

It also points to Multicom, but again, without any useful setup instructions.

Is using a serial cable even the correct one for Serial via Ethernet?

  • 2
    If you check your reference again, there is a hardware/software solution that would connect to the serial on your device and then to the network. You basically then open a TCP connection to that hardware solution. You do not directly connect your Ethernet port to the serial device.
    – YLearn
    May 27, 2015 at 14:31

1 Answer 1


Just because it fits doesn't make it a serial port. (Fibre Channel uses DB-9, but that's not RS-232 either!)

You'll need to find a USB/Serial adapter. Or find a "serial console server" (aka "terminal server") that is an ethernet device. (Digi PortServer, for example. Lots of people still make 'em.) In a pinch, you could use ye'old Cisco reverse telnet to make the aux port a "network serial port".


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