Ubuntu wireless debugging hints

have a look at

http://ubuntuforums.org/showthread.php?t=571188
https://help.ubuntu.com/community/LinuxLogFiles

test

ping www.google.com
ndislookup www.google.com
ping 209.85.227.99

debug network manager
sudo /etc/init.d/NetworkManager stop
sudo NetworkManager --no-daemon

disable/give up dhcp lease
sudo ifconfig eth1 down
sudo dhclient -r eth1

unencrypted by hand
sudo iwconfig
sudo iwlist eth1 scan

sudo iwconfig eth1 channel 1
sudo iwconfig eth1 mode managed
sudo iwconfig eth1 essid KP
sudo dhclient

wpa-psk [TKIP]
sudo wpa_supplicant -Dwext -ieth1 -c/etc/wpa_supplicant.conf -dd &
sudo dhclient eth1

--------contents of /etc/wpa_supplicant.conf
ap_scan=1
ctrl_interface=/var/run/wpa_supplicant

network={
ssid="KP"
scan_ssid=0
proto=WPA
key_mgmt=WPA-PSK
psk="password here"
pairwise=TKIP
group=TKIP
}
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