Re: WAP54Gs with WPA not handing out IPs from SBS2003 server

On 26 May 2006 14:50:06 -0700, "NeoMagick" <neomagick@xxxxxxxxx>
wrote:

I've got 4 laptops which aren't able to pull IP
addresses. They find the wireless network, they connect (using the PSK
over WPA), and then they sit trying to obtain IP addys for (seemingly)
days.

I'll assume you're running Windoze XP Home using Wireless Zero Config
and the latest WAP54G v3 hardware.

XP wireless is stupid. There's little connection progress indication.
Waiting forever for a DHCP delivered IP address is usually either an
encryption key exchange failure, or for WPA-PSK, an authentication
failure. I can also be the inability of the WAP54G to pass broadcasts
from the SBS2003 DHCP server. The large variety of laptops that don't
work points to problem with the WAP54G.

Dumb questions:
- Are you using WPA-PSK or WPA2-PSK?
- Are there any MAC or IP filters running in the WAP54G?
- SBS2003 Standard or Premium edition?
- Do you have enough IP addresses in the DHCP pool on the DHCP server?
- Is the SBS2003 DHCP server pre-filtering the clients by MAC address?
- Do you have some other form of security enabled on the SBS2003
server?
- Do you have the SBS2003 server setup with NAT using one or two
ethernet cards?

I vaguely recall that the WAP54 logviewer reports authentication
failures. I'm not sure. Go to the log page:
| http://www.linksysdata.com/ui/WAP54G/v3/3.01/Setup.htm
Enable logging. Either point it to a machine running the crude
Linksys logviewer or hit "view log" button.

Windoze XP has a WZC debugging log feature that will bury you in
diagnostics.
| http://www.microsoft.com/technet/prodtechnol/winxppro/maintain/wlansupp.mspx
| http://www.microsoft.com/technet/prodtechnol/winxppro/maintain/wifitrbl.mspx
I'm fairly sure you'll find some kind of authentication failure in
there.

The machines that were having issues were all Dells, until my laptop
(an HP) took on the same symptoms today.

Reading between your lines, you mention that your HP laptop apparently
worked before, but now doesn't. That sounds like running out of IP's
in the DHCP pool. (Hint: If you mention that something changes,
kindly disclose what it changed from).

I have also discovered that plugging in a Netgear PCMCIA card will
allow one the computers (the Inspiron 6000) to connect right away, no
questions asked. Pop the same card into the Latitude D620, and I've
got the problem again.

So much for the DHCP IP pool theory. Moving a MAC address (on a card)
from one machine to another should also move the IP addresses as the
ARP table is unchanged. Weird(tm).

The WAPs are each configured as Access Points,
rather than bridges, repeaters, etc. I've taken one of the APs and
made it a seperate SSID as a testbed to find out wtf is going on. I
can reproduce the problem no matter what length key, how often the key
renews, TKIP or AES, SSID, or channel we use.

Can you find another DHCP server other than the SBS2003 server?

- The APs /do/ work - most computers can connect without issue.

How many computers? Over 253 machines? If exactly 30 functional
machines per WAP54G, I think I have a good guess (but no fix).

- When I drop encryption, either entirely or down to WEP, the computers
that are having issues can connect without fail.

OK, so it's encryption compatibility. I'm currently having problems
getting WPA2-PSK to play with an eclectic mix of hardware. When I
went down to WPA-PSK, everything was fine. Weird(tm). Since DHCP
works with no encryption, it's a fair bet that it's not a DHCP issue.

- As soon as we bring up WPA, either with TKIP or AES, the trouble is
reproducable.

WPA or WPA2?

- All the computers are using the latest drivers, bios revisions,
firmware, etc.
- The APs are using the latest firmware (3.04)

OK. 3.04 is the latest for WAP54G v3 hardware.
Did you try a hard reset after upgrading the WAP54G firmware?

- When I use a PCMCIA card on the Dell Inspiron 6000, it works fine
- When I use the same PCMCIA card on the Dell Latitude D620, it has the
same problem.

Yeah, but are you using Windoze Wireless Zero Config to do the
wireless connection or are you using whatever came with your PCMCIA
card? Uncheck "Let Windoze manage this device" to let the
manufacturers driver take control.

- Linksys Tech-to-Tech Partner support, and the Dell Gold Support
department (and their support people) are all stumped. The Linksys guy
I talked to said he saw the problem once, but bringing it up to the
latest drivers/firmware fixed it. No joy this time.

Anyone seen anything like this? Anyone have any suggestions? We're
boggled over here.

I've seem similar problems, but not quite a weird as this.

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