Re: [Etherboot-developers] Wake-on-LAN patch

[Markus G. <ma...@gu...>]

> Well, as I understand it, broadcast is only in the sense of the
> encapsulating packet. A WOL packet can be embedded in any type of
> packet, even non-IP packets.  However the WOL packet itself has to
> contain the MAC address of the targetted server. If it were not
> specified that way a broadcast WOL packet would wake up all sleeping
> servers on the network segment, whether you intended to or not.

For some users, that might be acceptable. It really depends on how
you set up your network. Also, a multicast packet (if we can figure
out how to set that up) would avoid the problem of waking up
everybody. Now, whether broadcasting and multicasting the WOL
information works is something that I cannot really tell without
access to the official documentation -- and probably testing whether
anybody bothers to implement the full specs. Intel's web site made
it sound as if their NICs could listen for broadcast WOL packets,
but didn't handle multicast. Again, all of this is only useful to
users who are in the (admittedly unusual) situation of wanting the
client to wake up the server. I think, offering the option of doing
this is interesting (either as a patch in contrib, or as part of the
official tree), but only if it can be done in a generic way. Consider
all of the above as me brainstorming about how to offer a generically
useful solution.


Markus

-- 
Markus Gutschke                                Resonate, Inc.
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