Wireless DHCP issues

Werner Almesberger werner at openmoko.org
Tue Feb 3 07:42:22 CET 2009

"Marco Trevisan (Trevi??o)" wrote:
> I wanted to understand better this by running a packet sniffer while my
> notebook was in monitor-mode to understand what's happening, but I had
> no time (and who knows when I'll have :().

Yes, this looks like the kind of problem that could benefit from a
little sniffing.

Oh, and in case you're considering tcpdump for this, please use
airodump-ng instead. tcpdump subtly mis-decodes the 802.11 packets
it captures, guaranteeing no end of fun when trying to make sense
of the resulting mess ...

Maybe check if  wmiconfig -i eth0 --power maxperf  does something.
After all, we know that it has some mysterious but apparently very
reproducible effect on this kind of oddities.

> Werner, maybe have you done some research about this too?

I have yet to encounter a scenario where one protocol would pass
but others don't, e.g., everything but DHCP in your case or John
Sullivan's black hole for ICMP echo.

The usual explanation would be a broken firewall configuration
somewhere, but that doesn't quite fit in these cases ...

- Werner

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