I tried to install Zyx2250 but no luck.  The adapter I am playing is not on elinux's verified list.  I wonder if I should try an verified thing and test again.

Zyxel 2250 USB Wireless Adapter installation v1.0 [Failure!!!] - tlfong01 2013apr10

Hardware configuration

sudo powerdo

References

http://elinux.org/RPi_Peripherals#Wireless:_TP-Link_TL-WN722N_USB_wireless_adapter_.28Debian_6.29
http://www.element14.com/community/docs/DOC-44703/l/raspberry-pi-wifi-adapter-testing
http://omer.me/2012/04/setting-up-wireless-networks-under-debian-on-raspberry-pi/


1. Edit the file /etc/apt/sources.list to add the non-free archive and backports.

deb http://ftp.us.debian.org/debian/ squeeze main non-free
deb http://security.debian.org/ squeeze/updates main non-free
deb http://ftp.us.debian.org/debian/ squeeze-updates main non-free
deb http://backports.debian.org/debian-backports squeeze-backports main non-free


[Listing of /etc/apt/sources.list]
deb http://mirrordirector.raspbian.org/raspbian/ wheezy main contrib non-free rpi
deb http://ftp.us.debian.org/debian/ squeeze main non-free
deb http://security.debian.org/ squeeze/updates main non-free
deb http://ftp.us.debian.org/debian/ squeeze-updates main non-free
deb http://backports.debian.org/debian-backports squeeze-backports main non-free
[End of listing]

2. Update the package cache.

$ sudo apt-get update

[Takes a couple of minutes, with 12 "404 Not found ..." errors.]


3. Download the wifi utils:

$ sudo apt-get install wireless-tools usbutils


4. Download USB wireless adapter driver.

[This step is not required for Zyxel 2250.]


5. Edit the file /etc/network/interfaces to add wlan0 section.  This is used by Used by ifup(8) and

ifdown(8). See the interfaces(5) manpage or /usr/share/doc/ifupdown/examples for more information.

auto lo
iface lo inet loopback
iface eth0 inet dhcp

# The wireless interface
auto wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa.conf


[*** The file already contains a section starting with "allow-hotplug wlan0".  Not sure if
this section should be commented out, or should go before the "auto wlan0"sudo  section to be

added.]

auto lo

iface lo inet loopback
iface eth0 inet dhcp

allow-hotplug wlan0
iface wlan0 inet manual
wpa-roam /etc/wpa_supplicant/wpa_supplicant.conf
iface default inet static
address 192.168.1.40
netmask 255.255.255.0
gateway 192.168.1.1

# The wireless interface
auto wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa.conf

[*** End of listing ***]


6. Plug in adapter and confirm it is present and doing something.

$ sudo iwconfig

[*** message listing ***]

lo - no wireless extensions.

etho - no wireless extensions.


wlan0 unassociated ...
...


[*** End of message ***]


7. Scan network to confirm the adapter is doing something and see what wireless access points can

be seen.

$ sudo iwlist wlan0 scan | grep ESSID [for a short report] or

$ sudo iwlist wlan0 scan [for a long report]

[*** Message listing ***]

ESSID: "tlfong01"
ESSID: "John Chan"
...

[*** End of message listing ***]


8. Create the file /etc/wpa.conf with the follow data.

network={
ssid="NETWORK-SSID"
proto=RSN
key_mgmt=WPA-PSK
pairwise=CCMP TKIP
group=CCMP TKIP
psk="WLAN-PASSWORD"
}

[*** File listing ***]
network={
ssid="tlfong01"
proto=RSN
key_mgmt=WPA-PSK
pairwise=CCMP TKIP
group=CCMP TKIP
psk="220501"
}
{*** End of file listing ***]


9. Start the adapter

$ sudo ifup wlan0

[*** Message listing ***]
...
No DHCPOFFERS received.
Unable to obtain a lease on first try. Exiting.
Failed to bring up wlan0.


10. Check if connected to WLAN.

$ ifconfig

eth0 ...

lo ...

wlan0 ...


11.  If fail to connect, read the systme error messages.

$ cat /var/log/messages

Notes

1.  The above test has the Cat 5 ethernet cable connected.  Below is testing again with the

ethernet cable disconnected, and rebooting.

.END