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On Friday 25 June 2010 18:52:18 Enrico Weigelt wrote: |
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> Hi folks, |
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> |
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> |
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> my Atheros wlan (builtin, internal intenna) is regularily |
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> loosing link. Reproducible in various different networks. |
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> At home, my wlan ap is about 2 meter away (within the room), |
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> so link quality (currently 53) shouldnt be the problem. |
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> |
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> Does anyone know what could cause the problem ? |
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> |
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> # cat /proc/version |
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> |
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> Linux version 2.6.31-gentoo-r10 (root@×××××××××.local) \ |
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> (gcc version 4.3.4 (Gentoo 4.3.4 p1.0, pie-10.1.5) ) \ |
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> #1 SMP Wed Jun 2 00:51:13 CEST 2010 |
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> |
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> # lspci -v |
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> ... |
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> |
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> 02:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless |
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> Network Adapter (PCI-Express) (rev 01) Subsystem: Askey Computer Corp. |
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> Device 7167 |
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> Flags: bus master, fast devsel, latency 0, IRQ 16 |
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> Memory at f6000000 (64-bit, non-prefetchable) [size=64K] |
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> Capabilities: [40] Power Management version 3 |
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> Capabilities: [50] MSI: Enable- Count=1/1 Maskable- 64bit- |
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> Capabilities: [60] Express Legacy Endpoint, MSI 00 |
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> Capabilities: [100] Advanced Error Reporting |
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> Capabilities: [140] Virtual Channel <?> |
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> Capabilities: [160] Device Serial Number 00-15-17-ff-ff-24-14-12 |
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> Capabilities: [170] Power Budgeting <?> |
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> Kernel driver in use: ath9k |
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> Kernel modules: ath9k |
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> ... |
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> |
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> |
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> Jun 25 19:36:51 excalibur kernel: wlan0: no probe response from AP |
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> 00:23:08:86:d6:8f - disassociating Jun 25 19:36:51 excalibur |
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> dhcpcd[10182]: wlan0: carrier lost |
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|
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I have seen the same problem with my internal broadcom card and of course a |
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different driver. If you check google there seem to be pages and pages of |
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users reporting such a problem on different distros and with different makes |
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of wireless cards. |
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|
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The jury's out as to what's causing this. Is it related to modern cards with |
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low power management capabilities and how this may interact with the kernel, |
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or is it something to do with the tolerance built into TTL packets between the |
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card and the AP? |
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|
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With regards to my card I have noticed that at home I stay connected for hours |
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on end, at work it's a miracle if I stay online for longer than 5 minutes |
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(both on the same channel). This to me says that the problem is one of |
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interaction with the router, which points to tolerance on the TTL packets. |
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|
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Of course YMMV ... |
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-- |
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Regards, |
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Mick |
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