Thanks all for the very useful responses. 

I believe this "Radio Loses WiFi Connection" issue to be so serious as
to deserve major escalation. My 6 radios are very nearly unusable, most
failing after just a few minutes. Of course, not everyone is
experiencing this yet, but enough have so far and the numbers likely
will just keep growing. The entire ecosystem is threatened if the radios
fail in large number.

I tried turning everything off except for one new simple wireless AP,
the main router, and the pc running LMS, including phones, cameras,
televisions, IOT devices, and Bluetooth devices. Still, the radios wifi
deteriorated and eventually lost connectivity. This suggests RFI of some
sort disrupting the system, or that 6 radios on one access point is too
many. However, these radios have been around for years, but this
disconnection issue started only earlier this year, and has gotten worse
during the summer.

The neighbors are not that close, and their wifi signals are at least
20-30 db lower. I haven't gotten out the (quite heavy) spectrum analyzer
yet to look for interference, but it looks like that might be necessary.
I shouldn't need an LNA to detect what is presumably a high level
signal.

I tried setting the debugging flags, to increase the driver verbosity,
but these had no effect (because the ar6000.ko driver was build without
debug support?). However, a debug build may be needed.

Despite time spent, I have not made much or any progress with this
issue, being impeded by lack of the AR6102 chip specs and the source
code (no access to this site's private repository.) The closest public
source so far is some AR6kSDK.build_sw.18 code and various versions of
AR6kSDK.3.1, some of which is close to but not the same as the code
referenced in the various patch files. The various open source
decompilers produce dubious looking gibberish.

To reiterate, I see three issues: the device is too easily disrupted,
fails to report a connection loss, and the supplicant or other layer
does not otherwise notice a lack of connectivity and initiate corrective
action. An optimum response would be to address all three.

I examined the serial console log file started after over a day of
disconnection. In this session, the radio is connected to a simple bgn
router/access point located very close to the 4 of the 6 radios used by
the 'important' (no, not me) users. The rssi of this access point at the
test radio is 25 db below another modern AP 10 feet away. The bgn AP is
on channel 1, which somehow greatly improved its chances of being
detected by the ar6000 scan, and presumably connectivity, although not
enough. Connected to the office AP, the SB radio is more stable.
However, its UE office mate, 30 feet away from the same AP, drops out
anyway after a few minutes, so rssi is not the only factor. 

The 'wpa_cli scan_results' frequently show only 1 to 3 access points,
that is, the three nearby access points are frequently not all shown
even though the signal strengths are all good to excellent.
Occasionally, a neighbor's AP shows up, even though its signal strength
is 20 db less than the lowest house AP. Also, the connected AP sometimes
doesn't show up in the scan, a clue.

I then switched each radio to the strongest AP signal, on the three APs,
but they still kept dropping out after a few minutes, except the UE in
the basement, and the one with the serial cable connection, which last
much longer.

Out of frustration, I concocted a script to ping the gateway, and reset
the wireless when connectivity is lost. I cannot yet predict from the
statistics (e.g., when the errors skyrocket and/or the data rates
decline) when connectivity will be lost. So it's the ping method, which
is reactive and result in an outage of several seconds. This should be
handled by the supplicant, or other service, but since that is not
working, this is a start.

Some good news: "wpa_cli reassociate" restores connectivity in many, but
not all, cases. It works fairly quickly, when it works. 

And, my script has been running on my 6 radios, and they are still
connected, a big success!


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View this thread: http://forums.slimdevices.com/showthread.php?t=111663

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