[SOLVED]wlanwep encryption is failing after system update(pacman -Syu)

Question

After a system update with "pacman -Syu" my wlan encryption does not work anymore.
If I switch off encryption on my access point, I can communicate without any problems.
I have currently two wlans active, one with encryption, one without. I use the following iwconfig settings
iwconfig wlan0 essid my_open_wlan
iwconfig wlan0 essid my_wep_wlan key s:my_wep_password
In the first case I get the connection, in the second I cannot transmit over the network(Destination Host Unreachable).
lspci:
07:00.0 Network controller: Atheros Communications Inc. AR9287 Wireless Network Adapter (PCI-Express) (rev 01)
iwconfig:
wlan0 IEEE 802.11bgn ESSID:"wlan_2012"
Mode:Managed Frequency:2.437 GHz Access Point: 00:04:0E:57:4E:27
Bit Rate=1 Mb/s Tx-Power=13 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=39/70 Signal level=-71 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:44 Invalid misc:43 Missed beacon:0
ip addr:
3: wlan0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
link/ether ec:55:f9:1d:bf:41 brd ff:ff:ff:ff:ff:ff
inet 192.168.1.11/24 brd 192.168.1.255 scope global wlan0
inet6 fe80::ee55:f9ff:fe1d:bf41/64 scope link
valid_lft forever preferred_lft forever
This is the output for the open wlan. If I try to connect to the encrypted wlan with "iwconfig wlan0 essid "my_encr_wlan" key s:my_wep_password", the iwconfig command gives me:
wlan0 IEEE 802.11bgn ESSID:"wlan_2007"
Mode:Managed Frequency:2.452 GHz Access Point: D8:5D:4C:FA:24:0D
Bit Rate=5.5 Mb/s Tx-Power=13 dBm
Retry long limit:7 RTS thr:off Fragment thr:off
Power Management:off
Link Quality=33/70 Signal level=-77 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:2 Invalid misc:1 Missed beacon:0
I have tried wpa_supplicant as well with the same result.
Can anybody give me hint?
Regards
Helmut
Last edited by helmut (2012-03-05 16:31:25)

Answer 1

Wep and ath9k has been buggy for me for a long time now - sometimes it works, sometimes it doesn't. Never got around it, adding "options ath9k nohwcrypt=1" into /etc/modprobe.d/ath9k.conf seemed to work for some time. You could give it a try. The network I have problems with is at the university, they use wep + vpn to connect. I can connect fine (like in your last iwconfig), but dhcpd times out.
If you have control over the network, you could just switch to wpa - safer anyway. Or search the forum for "atheros wep", it is a somewhat common problem I think.
P.S.: please use code tags when posting console output.
Last edited by hokasch (2012-02-18 14:48:24)