Wireless DHCP issues
"Marco Trevisan (Treviño)"
mail at 3v1n0.net
Tue Feb 3 05:20:56 CET 2009
Hello since long time (always I guess) I have had problems when I tried
to get an IP using DHCP from some APs.
At the beginning I thought that this was just an issue of one of my
wireless routers (a Motorola WR850GP running dd-wrt), but recently I
verified that I was unable to make the DHCP working with many free APs I
tried (at the university, at the pub...).
Practically, I associate with the AP (iwconfig confirms me it, but also
the AP), but when I try to get an IP I simply don't get any dhcp-offer
(or the phone doesn't grab it!), as you can see:
root at om-gta02:~# udhcpc eth0
udhcpc (v1.11.1) started
root at om-gta02:~# dhclient eth0
Internet Systems Consortium DHCP Client V3.0.2
Copyright 2004 Internet Systems Consortium.
All rights reserved.
For info, please visit http://www.isc.org/products/DHCP
Listening on LPF/eth0/00:12:cf:8e:ef:4b
Sending on LPF/eth0/00:12:cf:8e:ef:4b
Sending on Socket/fallback
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 4
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 6
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 14
DHCPDISCOVER on eth0 to 255.255.255.255 port 67 interval 15
If now I configure my network manually with ifconfig, route, resolv.conf
(if I know the needed informations) as expected - I can connect with no
So, the wireless association works well with any router. With some ones,
unfortunately, I can't use the DHCP (also if, of course, the router
supports it and I am able to get an IP using another device).
I've tested this with Om2008, Debian, Android... Every distro has the
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 :().
Werner, maybe have you done some research about this too?
Treviño's World - Life and Linux
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