On Saturday 26 June 2010 14.35.28 Mick wrote: > On Friday 25 June 2010 18:52:18 Enrico Weigelt wrote: > > Hi folks, > > > > > > my Atheros wlan (builtin, internal intenna) is regularily > > loosing link. Reproducible in various different networks. > > At home, my wlan ap is about 2 meter away (within the room), > > so link quality (currently 53) shouldnt be the problem. > > > > Does anyone know what could cause the problem ? > > > > # cat /proc/version > > > > Linux version 2.6.31-gentoo-r10 (r...@excalibur.local) \ > > (gcc version 4.3.4 (Gentoo 4.3.4 p1.0, pie-10.1.5) ) \ > > #1 SMP Wed Jun 2 00:51:13 CEST 2010 > > > > # lspci -v > > ... > > > > 02:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless > > Network Adapter (PCI-Express) (rev 01) Subsystem: Askey Computer Corp. > > Device 7167 > > > > Flags: bus master, fast devsel, latency 0, IRQ 16 > > Memory at f6000000 (64-bit, non-prefetchable) [size=64K] > > Capabilities: [40] Power Management version 3 > > Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit- > > Capabilities: [60] Express Legacy Endpoint, MSI 00 > > Capabilities: [100] Advanced Error Reporting > > Capabilities: [140] Virtual Channel <?> > > Capabilities: [160] Device Serial Number 00-15-17-ff-ff-24-14-12 > > Capabilities: [170] Power Budgeting <?> > > Kernel driver in use: ath9k > > Kernel modules: ath9k > > > > ... > > > > > > Jun 25 19:36:51 excalibur kernel: wlan0: no probe response from AP > > 00:23:08:86:d6:8f - disassociating Jun 25 19:36:51 excalibur > > dhcpcd[10182]: wlan0: carrier lost > > I have seen the same problem with my internal broadcom card and of course a > different driver. If you check google there seem to be pages and pages of > users reporting such a problem on different distros and with different > makes of wireless cards. > > The jury's out as to what's causing this. Is it related to modern cards > with low power management capabilities and how this may interact with the > kernel, or is it something to do with the tolerance built into TTL packets > between the card and the AP? > > With regards to my card I have noticed that at home I stay connected for > hours on end, at work it's a miracle if I stay online for longer than 5 > minutes (both on the same channel). This to me says that the problem is > one of interaction with the router, which points to tolerance on the TTL > packets. > > Of course YMMV ...
Last time I had this problem I tracked it to a conflict between wpa_supplicant and the card driver. Basicly the card driver would send a request to assosiate with mac 00:00:....:00 each time a new card was found on the air and wpa_supplicatnt interpreted this as a request from the driver to drop the connection. The driver folks said that this request should be ignored and the wpa_supplicant folks said that this should not be ignored but instead was a disconnect request. Catch 22... Because of this I had to use wep instead of wpa(2) for along time. /Naga
