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Old 03-15-2008, 12:40 PM   #1
Registered: Feb 2008
Posts: 40

Rep: Reputation: 15
iwlist no scan results: wlan0 still worked


I use a hp compaq nx9020 with a Belkin Wlan pci card.

The Wlan was still working fine for weeks but yesterday it suddenly stopped while using rtorrent.

Therefore I don't think it is config problem.
I installed the driver through ndiswrapper.

I don't know why but I can't change my essid.

Link Quality: 0 Signal level: 0 -> looks strange. looks like there is no signal.
Is there a possibility to check if the rooter is sending any signals?
The "Wlan led" on my Belking rooter is on and blinking.

#iwlist wlan0 scanning

wlan0 No scan results

#iwconfig wlan0

wlan0 IEEE 802.11g ESSIDff/any Nickname:"zenwalk"
Mode:Managed Frequency:2.462 GHz Access Point: Not-Associated
Bit Rate=54 Mb/s Tx-Power:14 dBm
RTS thr=2347 B Fragment thr=2346 B
Encryption keyff
Power Managementff
Link Quality:0 Signal level:0 Noise level:0
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

If I run wpa_supplicant it shows the followinng output.
#wpa_supplicant -i wlan0 -c /etc/wpa_supplincant/ -Dwext -d
Added interface wlan0
RTM_NEWLINK: operstate=0 ifi_flags=0x1002 ()
Wireless event: cmd=0x8b06 len=8
RTM_NEWLINK: operstate=0 ifi_flags=0x1003 ([UP])
RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added
Starting AP scan (broadcast SSID)
Trying to get current scan results first without requesting a new scan to speed up initial association
Received 0 bytes of scan results (0 BSSes)
Scan results: 0
Selecting BSS from priority group 0
Try to find WPA-enabled AP
Try to find non-WPA AP
No suitable AP found.
Setting scan request: 0 sec 0 usec
Starting AP scan (broadcast SSID)
Scan timeout - try to get results
Received 0 bytes of scan results (0 BSSes)
Scan results: 0
Selecting BSS from priority group 0
Try to find WPA-enabled AP
Try to find non-WPA AP
No suitable AP found.
Setting scan request: 5 sec 0 usec

I appreciate any help!



Last edited by clementis; 03-15-2008 at 01:35 PM.
Old 03-16-2008, 07:28 AM   #2
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Registered: Nov 2005
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How did you try changing the ESSID?

Does the ESSID in the iwconfig output look like the one set in the router?

Without WPA, you can explicitly setting the parameters like so (look at the iwconfig man page for details on WPA):

iwconfig wlan0 essid xxxx channel x key s:xxxx
(replace the xs with your actual values---note the "s:" in the key--required for text (ascii) keys)

dhcpcd wlan0
to connect
Old 03-24-2008, 05:20 AM   #3
Registered: Feb 2008
Posts: 40

Original Poster
Rep: Reputation: 15
Thank you pixellany!

Now my Wlan works fine.

I tried to change the essid like so:
# iwconfig essid "myessid" channel 11

# dhcpcd wlan0
I got no lease, instead I got an IPv4 adress.

# ping
PING ( 56(84) bytes of data.
64 bytes from icmp_seq=1 ttl=64 time=1.55 ms
64 bytes from icmp_seq=2 ttl=64 time=26.5 ms

The ping looked strange because I received data form instead of

I did the follwing:

1. I unpluged the Lan cable
2. rebooted
3. turned of the eth1
# ifconfig eth1 down
4. killed wpa_supplicant and dhcpcd
5. restarted wpa_supplicant and dhcpcd
# wpa_supplicant -i wlan0 -c /etc/wpa_supplincant/ -Dwext -d
# dhcpcd wlan0 -L

I'm not sure what the problem was, but this worked for me.



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