Wake-on-lan packages don't get through
fb-embedded at psconsult.nl
Tue Dec 16 11:29:49 PST 2008
On Tue, Dec 16, 2008 at 07:22:39PM +0100, Markus Hitter wrote:
> Hello all,
> glad to have found a binary wake-on-lan program, I obvserve different
> behaviour of /usr/bin/wol on my full-size FreeBSD and my TinyBSD. From the
> full-size BSD (VirtualBox on Linux), i could capture this package after
> issueing wol:
> 18:50:30.019039 IP (tos 0x0, ttl 64, id 0, offset 0, flags [DF], proto UDP
> (17), length 130) piccard.jump-ing.de.37597 > 255.255.255.255.40000: [bad
> udp cksum b716!] UDP, length 102
> This package woke the targeted Macintosh. Doing the same on the embedded
> Flepo, I get:
> 01:38:35.500497 IP (tos 0x0, ttl 64, id 40022, offset 0, flags [none],
> proto UDP (17), length 130, bad cksum 0 (->d401)!) git.jump-ing.de.50582 >
> 255.255.255.255.40000: [bad udp cksum a1e4!] UDP, length 102
> The later doesn't get through the switch, I can capture it on the sending
> host only. Accordingly, the Mac keeps sleeping.
Please show a tcpdump -e output here. The wake-on-lan packet should
be sent to the ethernet broadcast address (ff:ff:ff:ff:ff:ff) for the
switch to send it to all ports (which is needed since it can't learn mac
address from switched off nodes).
On some of my machines I need to explicitely send the packet to the
IP LAN broadcast address, e.g. 192.168.1.255 (assuming /24 netmask).
> As both "wol" binaries are the very same (copied), I can rule out
> compilation errors. To be more funny, the Flepo serves web pages just fine.
> What does go wrong here?
What about the kernels, are they the same version? and does your
embedded system have more than one ethernet interface?
> Thanks for any enlightenment,
>  Using wakeonlan requires Perl, which in turn would more than double the
> size of the installation on the embedded box.
> - - - - - - - - - - - - - - - - - - -
> Dipl. Ing. Markus Hitter
More information about the freebsd-embedded