Re: NM doesn't scan after powering on radio

[Dan Williams <dcbw redhat com>]

On Wed, 2009-12-16 at 16:53 -0500, Matthew Saltzman wrote:
> I suspended, turned off the radio with the hardware switch, resumed.
> The applet showed wireless disabled.  I suspended with the switch off,
> resumed (in a location different from my last connection, FWIW), and
> turned the switch off.  The applet showed wireless enabled, but NM did
> not initiate a scan at that point.  I restarted the NM service and all
> was well.

NM may well initiate a scan, but unfortunately there's no way for the
supplicant to report that the scan request failed (due to its internal
code structure), so NetworkManager doesn't know that it needs to request
another scan when the first one fails.  It turns out that some drivers
(especially ath5k) like to deny scans quite a bit.  We need more work in
this area, and we may be able to fix up the supplicant to provide "scan
failed" notifications that we can use but that'll take more work.

NM should, however, request another scan within 20 seconds or so.  But
of course if that one fails for some reason, then the next request won't
be for 40 seconds after that.

Dan