On 2018-02-07 02:36, Stefan Sperling wrote:
There is a known behaviour of the firmware where, on a 5 GHz channel,
it will not transmit a probe request unless it first sees some other
valid packet on the channel. This has to do with how the firmware deals
with regulatory domains, which restrict 5Ghz channels in some parts of
the world. I don't really understand exactly how it works, and how we
can control it. But there are some parameters which go into the scan
command which you could try tweaking to see if they have any effect,
and let us know your results.
Confirmed that this was the source of the behavior I was seeing.
Other devices were sending valid packets in my prior testing where the 5GHz
SSID was seen reliably.
I moved to the 6.2 snapshots at the same time as other devices stopped being
present.
Bringing the other devices back on line returns the 6.2 snapshots to almost
always working on 5GHz.
If you want to try playing with these parameters to the firmware,
(i.e. change them, recompile kernel, and test) you can find them
in if_iwnreg.h:
Thank you. I will try adjusting the active dwell times when I next have a
quiet 5GHz SSID.
Richard
