All Mac Pros / XServes have 2 gigabit wired NICs. It has always annoyed me that a: there is no way to bridge them (no BRCTL, et al. for Mac), and b: there is no way to "use" the second port, even internally, without a physically connected ethernet cable AND an active link at the other end!!
I would like to be able to use that "port" for internal DNS servers, VMWare guests, or whatever I damn well please.. without having to 1: find an ethernet cord, 2: a powered ethernet jack to plug the cord into, and 3: a powered jack that belongs to a device that won't be flooding the line with packets unrelated to what I'm trying to do.
- No combination of "sudo ifconfig en1 up" gets it done.
- I have looked through all the PMSET rules, and nothing applies to the ethernet power besides WOLP or whatever the wake-on-lan thing is called...
- I have slogged through the labryntine, and poorly documented SYSCTL options, with no apparent solution there.
- I have tried tricking it with various static IP assignments /VLAN configurations /duplicate adapters, to no avail.
- Googled it extensively. Plenty of ways to turn off ethernet when switching to airport, etc, but not this.
This is either a case of the hardware driver attempting to save power, or Apple willfully discouraging any creative uses of the hardware (which is why they virtually prohibit bridging at the kernel level (to maintain their router sales)), and I don't like it. Any idea how to force that sucker on?
There's no need to fake a physical network interface being active when you can create virtual network interfaces. TUN and TAP devices let you have as many IP or ethernet level devices as you need. The TunTap project provides the drivers for OS X.
Take this with a grain of salt, as I really don't know if this will kick the port on to the point that it'll be usable.. but a loopback end ought to do it.
Something like this, or just make your own if you have the tools (crimps and an end): one wire from port 1 to port 3, and another from port 2 to port 6.