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Re: How to load non-free firmware driver



Robert Parker wrote:
> But now when I connect to my wirelees access point it gives me a
> 'connecting' message and finally connects only to immediately drop
> out and start connecting all over again.

What configuration are you using to connect to it?  Are there any
clues to the problem in /var/log/syslog around the problem?  Basically
unless we see something it isn't going to be possible to help.  (And
unfortunately since you are the one seeing the problem it may not be
possible for us to guess correctly at the reason anyway.)

> My access point is unsecured, I don't know if that has any bearing
> on the problem.

In theory it shouldn't.  But the difference between theory and
practice is the difference between theory and practice.  Your device
is an Atheros and that has a good reputation.  YMMV.  Always worked
well for me.

There are several steps in the WiFi connection process.  Off the top
of my head:

1. Associate.
2. If DHCP is configured then perform DHCP protocol.

If your wifi is associating and immediately disassociating then there
could be a problem with the driver.  Try unloading and reloading the
driver.  This sometimes works for me and others on the list have
reported it similar.

  rmmod drivername ; sleep 1 ; modprobe drivername

If the wifi is associating okay then it will typically DHCP.  (Unless
a static configuration has been chosen.)  If the DHCP fails then the
device will be deconfigured.  If the device associates then it should
be able to transmit and receive dhcp packets.  If this is prevented
then dhcp will fail and the device will be deconfigured.  The dhcp
might fail if the device is not tranfering dhcp packets properly.  Or
if a firewall is blocking those packets.  If you have a firewall then
try the connection with the firewall disabled.

I often use tcpdump to try to capture the dhcp protocol but this is
trickier since the device is always going up and down.  For tcpdump
use the device "any" to listten to any configured network.  Another
useful tool is 'dhcpdump'.  But usually if packets are being
transfered then it will work and if packets are not being transferred
then it won't work.

It is also possible for all to work okay on the client end but to have
the dhcp on the server end to fail.  A typical failure configuration
is to have too few dynamic IP addresses available on the pool.  For
example one open wifi access point that I know at one of the local
airports has only 25 IP addresses in the pool.  It allocates those
addresses for 24 hours.  At 6am in the morning you can associate and
get an IP address.  By 10am in the morning all of the 25 IP addresses
have been allocated and leased for 24 hours.  They will not free up
again until the next day.  This is a misconfiguration of the wifi
access point's dhcp server configuration for the task that it is
trying to do but it creates this behavior of not being able to get
wifi access from it due to a server configuration issue even though
the client is okay.  (Workaround hack: If you know the configuration
then you can bypass DHCP and set a static configuration for it.)

This next item I am going to mention isn't really associated
particularly with wifi.  The DHCP will transfer routing information.
That is usually always good.  The DHCP will transfer nameserver
information.  This is sometimes troublesome.  If the nameserver is
broken then it leads to a confusing situation where the network
connection is established but no names can be looked up.  Since humans
generally deal with names it makes it appear as if the network is both
up and down at the same time.  If you hear people suggesting a
particular known good nameserver such as 8.8.8.8 that is the problem
they are addressing.  However I believe it is better to fix the real
underlying problem rather than work around it.

Good luck!
Bob

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