Pardon me if I missed the clarification, but if one XO unit is
consistently bad while another physical XO unit always works regardless
of their locations, this would suggest a hardware issue.
Your truncated "scan-wifi" output suggests that the bad XOs only were
working on Channel 1. I'd be curious to see if the bad XOs could talk
to good XOs on all 3 mesh channels (1, 6 & 11) even if placed a decent
distance apart. These appear as separate mesh icons you can connect to
manually in Sugar.
Although this may not apply to your case, from observation I have
noticed that "scan-wifi" provides very few (5-8, varying between runs)
results on an XO in an urban city, while "iwlist eth0 scan" typically
finds 25-40 Access Points per scan. Run repetitively, the AP I want to
connect to often appears in a single iwlist scan, but often does not
appear as well.
Using an 802.11 monitoring tool on a non-XO finds 100 APs are nearby in
~15 seconds with that number going over 200 within a few minutes. While
your environment may not be as extreme, if iwlist shows you have a lot
of APs in your area or you know there are other 2.4 GHz devices in use,
this may be part of the problem.
---
SJG
On 11/29/2010 9:21 PM, Mikus Grinbergs wrote:
Quozl wrote:
>> A symptom that I frequently observe is that 'iwlist eth0 scan'
>> (as root) does not show the radio signals that other XO_1s do show.
> Use scan-wifi in OpenFirmware in order to exclude the operating
> system configuration from the problem.
Thank you, thank you, thank you. This gives me a 'starting point'.
To 'scan-wifi', the "bad" XO-1s return lines like this:
RSSI: 0 SSID: Channel 1
...
RSSI: 0 SSID: Channel 1
RSSI: 41 SSID: Channel 1
To 'scan-wifi', the "good" XO-1s return lines like this:
RSSI: 0 SSID: Channel 1
...<more such lines than the "bad" XO-1s>
RSSI: 0 SSID: Channel 1
RSSI: 85 SSID: 2WIRE241 Channel 11
Note that both the "bad" XO1-s and the "good" XO-1s __will__ connect
via
the (non-adhoc) mesh interface -- to me that says the silicon is working
-- though I do not know if the AP radio signal in the "bad" XO-1s is too
attenuated (bad antenna connection?) to be detected.
Thanks again, mikus
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