Disable USB on ALIX 2D3
I'm running 1.2.3-RELEASE (embedded) on an ALIX 2D3 (500MHz/256MB), which has the standard 2 USB ports soldered on.
Running "usbdevs -v" tells me the USB ports are available. I don't use USB so, going by the principle that if it ain't in use it should be turned off, I'm trying to disable USB.
The ALIX BIOS has no USB options (and also can't boot from USB - I think that's a good thing in a firewall!). Running "kldstat" tells me that there's only one module (glxsb.ko) so it looks like USB support is compiled into the kernel - therefore, unloading/blacklisting the module is not possible. I'm not a FreeBSD expert (though I muck about with Linux a fair bit), and that's about the limit of my knowledge on the issue.
So, how do I disable USB?
Short of being able to do it in the BIOS, or building your own kernel without it, you can't.
There's no real incentive to disable USB if you aren't using it on ALIX. It isn't sharing an interrupt with anything (at least on mine it isn't), and there may be a case in the future where you need to access a file on a USB drive for some reason.
Some devices in FreeBSD can be disabled via device hints in /boot/device.hints but I don't think USB or the related drivers are among those (usb, uhub, ohci, ehci, etc).
Thanks for the tips, especially device.hints … but, you're right, there doesn't seem to be any reference to USB drivers in there.
I can live with USB being enabled, since one has to be root to mount anything, but I prefer to "tie up loose ends" when configuring security devices.