wifi in AP mode unreliable

[Klaus Darilion]

Hi!

My setup is Debian Squeeze with 2.6.32 kernel (from unstable) with 
hostapd 0.6.9. My wifi card is a Wistron CM9 (Atheros AR5213A) running 
in AP mode. Wifi interface wlan0 is together with eth1 in a bridge 
called lan0.

The problem is, that wifi is unreliable (comes and goes). I tested with 
multiple Windows notebooks as clients, all showing the same stability 
problems. Thus, the problem must be the access point.

I tested unencrypted and WPA2 mode, both are not stable.

Actually I do not know how to proceed further.
1. Where is the problem - in the kernel module (ath5k ?, ...?) or in hostapd
2. Any hints how to further debug this issue?

Here is my hostapd.conf:
------------------------------------
interface=wlan0
driver=nl80211
ssid=alix1
channel=11
bridge=lan0
hw_mode=g
# remove for WPA2
#macaddr_acl=0
#auth_algs=1
#ignore_broadcast_ssid=0
#wpa=2
#wpa_passphrase=holidayonice
#wpa_key_mgmt=WPA-PSK
#wpa_pairwise=TKIP
#rsn_pairwise=CCMP


syslog says:
19:53:55 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: authenticated
19:53:55 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: associated 
(aid 1)
19:53:55 hostapd: wlan0: STA 00:90:4b:1a:77:cd RADIUS: starting 
accounting session 4B4F75F9-00000000
19:53:55 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: pairwise key 
handshake completed (RSN)
20:02:25 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: group key handshake 
completed (RSN)
20:12:25 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: group key handshake 
completed (RSN)
20:21:29 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: authenticated
20:21:29 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: associated 
(aid 1)
20:21:30 hostapd: wlan0: STA 00:90:4b:1a:77:cd RADIUS: starting 
accounting session 4B4F75F9-00000001
20:21:30 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: pairwise key 
handshake completed (RSN)
20:22:02 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: disassociated
20:22:03 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: 
deauthenticated due to inactivity
20:22:12 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: authenticated
20:22:12 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: associated 
(aid 1)
20:22:12 hostapd: wlan0: STA 00:90:4b:1a:77:cd RADIUS: starting 
accounting session 4B4F75F9-00000002
20:22:12 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: pairwise key 
handshake completed (RSN)
20:22:25 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: group key handshake 
completed (RSN)
20:32:26 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: group key handshake 
completed (RSN)
20:38:04 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: authenticated
20:38:04 hostapd: wlan0: STA 00:90:4b:1a:77:cd IEEE 802.11: associated 
(aid 1)
20:38:04 hostapd: wlan0: STA 00:90:4b:1a:77:cd RADIUS: starting 
accounting session 4B4F75F9-00000003
20:38:04 hostapd: wlan0: STA 00:90:4b:1a:77:cd WPA: pairwise key 
handshake completed (RSN)


The only suspicious things I see is:
IEEE 802.11: disassociated
IEEE 802.11: deauthenticated due to inactivity

Is this something normal? Or is there a problem?


thanks
klaus