Problem setting up wired networking

[Chuck Anderson]

On Fri, Nov 14, 2008 at 04:24:47PM +0000, Anne Wilson wrote:
> On Friday 14 November 2008 15:33:20 Chuck Anderson 
> Now that's a report I haven't seen before.  It appears that 
> neither my ESSID or key are being read from the file that 
> surely must be created when NM configures the 
> connection.

iwconfig is a low-level tool--it just shows or manually configures 
what is in the kernel driver for the wireless card.  It doesn't 
integrate with the configuration files or wpa_supplicant or 
NetworkManager at all.

> > iwlist scanning
> 
> As before - No  scan results.

Try repeating "iwlist scanning" a few times in a row--sometimes it 
takes a few tries for results to appear.

But, this seems like a kernel driver issue then, nothing to do with 
wpa_supplicant or NetworkManager.  To be sure, could you temporarily 
turn those off, reboot, and repeat those steps above?

chkconfig --level 2345 NetworkManager off

(wpa_supplicant should always be off by default anyway, but in case:
chkconfig --level 2345 wpa_supplicant off
don't turn it back on again after testing since it is launched 
automatically as needed by NM)

After testing, you can turn NetworkManager back on:

chkconfig --level 2345 NetworkManager on

This will help by eliminating NetworkManager or wpa_supplicant as the 
cause of "no scan results". 

Remeber to try "iwlist scanning" a few times in a row.


> Wow - some progress, if only small.  In view of what 
> appears above I renamed ifcfg-wlan0 and created a new 
> one.  I immediately got a popup saying that I am now 
> connected to myESSID.  BUT, the icon shows a very weak 
> signal, and ifconfig shows that it has the address 
> 10.42.44.1, while my network is a 192.168.0.x LAN.

Strange.

> This is the situation I reached a couple of days ago, and 
> I'm comopletely foxed by it.
> 
> Running iwconfig wlan0 again I now get
> 
> wlan0     IEEE 802.11bg  ESSID:"myESSID"
>           Mode:Ad-Hoc  Frequency:2.412 GHz  Cell: 
> 36:8F:3A:45:3F:BC
>           Tx-Power=27 dBm
>           Retry min limit:7   RTS thr:off   Fragment thr=2352 
> B
>           Power Management:off
>           Link Quality:0  Signal level:0  Noise level:0
>           Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid 
> frag:0
>           Tx excessive retries:0  Invalid misc:0   Missed 
> beacon:0
> 
> I tried changing the setup from ad-hoc to Infrastructure, 
> but that breaks things - I can no longer connect.

ad-hoc should only be for computer-to-computer connections, not 
computer-to-accesspoint.

> FWIW, my router does not list this netbook as a 
> connected device.

I'm guessing that you really didn't connect anywhere--you just created 
a new ad-hoc connection so that other computers could have connected 
to you on an ad-hoc basis.

Beyond the debugging of "scanning" above, you could ignore scanning 
and try to manually connect to a specific network.  With 
NetworkManager disabled:

iwconfig wlan0 essid myESSID
iwconfig wlan0 mode Managed
ifconfig wlan0 up

Now check a few times to see if it eventually associates to the AP:

iwconfig wlan0

Eventually, you should see it say "associated".  If that happens, you 
could try to get an IP address configured by manually starting the 
dhcp client:

dhclient wlan0


If you can repeatably connect fine using this method, then there is 
probably a problem with the kernel driver scanning for networks.  
NetworkManager won't work well if scanning doesn't work.


Some SELinux notes:

The above tests might work best with SELinux in permissive mode.

If you run in permissive mode for a while, your system may no longer 
have correct file labels.  After testing in permissive mode, when you 
are ready to switch back to enforcing mode, it is a good idea to:

touch /.autorelabel
reboot

To fix the labels on the entire system.