[mythtv-users] Wake-on-lan eureka!

[f-myth-users at media.mit.edu]

There are other things that might screw you if you don't know about
them as well.  Both of these have bitten me on certain motherboards,
in various combinations:

(a) Some chipsets require you to send the WoL packet to the -broadcast
Ethernet address-, rather than to the 48-bit MAC of the recipient, or
they apparently fail to notice the packet going by.  Typically you'd
use the -b flag to ether-wake to accomplish this.

(b) Some operating systems only work if the actual MAC address
embedded in the WoL packet (not the address to which it's sent) is
BYTE FOR BYTE REVERSED, e.g., BACKWARDS from the machine's actual MAC.
Counterintuitive?  For sure.  Obviously buggy?  You bet!

Here's a snippet from comments in one of my inits about this:

    # For some reason, the MSI/nVidia motherboards require using the broadcast address.
    # [This machine] is an MSI/VIA and doesn't require broadcast, but it doesn't hurt.
    #
    # And! under Breezy and Dapper, the MAC address must be -reversed- octet-by-octet
    # (e.g., aa:bb:cc:dd:ee:ff needs to be sent as ff:ee:dd:cc:bb:aa); this -might- be
    # because some bug in the nVidia controller that was correctly worked-around under
    # Hoary isn't any more.  Note that a machine that was booted under Hoary, or which
    # was powered-off from the BIOS before Ubuntu ever booted since power was applied,
    # can be sent to in normal order from another machine and -will- WoL, but that a
    # machine which ran Breezy or Dapper since poweron will -not- WoL unless the octet
    # order is reversed.

I'll note that an EPoX I have running Breezy (and I think Dapper) also
requires the reversed MAC, and that I think I recall hearing that this
isn't even fixed in Edgy/Fiesty, but that's hearsay to me 'cause I
haven't tested it.  FWIW, all of these are AMD CPUs.

I've also been unable to get either a ThinkPad X24 or a T23 to WoL no
matter what I do (and, alas, searching around hasn't yielded any clues),
though I suppose it's possible I've missed some crucial BIOS setting
(or, for that matter, some ACPI setting).  This is particularly
annoying because at least one of those machines would make a good
supervisory machine (low-power, cheap, has an internal battery in case
the UPSes are down, etc) and it'd sure be nice to be able to wake it
up on demand.  If anyone has clues, please dish.