Re: Problem when using 2 APs WAP54GP

pmachete@xxxxxxxxx hath wroth:

AP1 <-> HUB <-> AP2 <-> Laptop
|
PC

Here is when I start to have problems.
The connection to AP2 is fine and I can ping it. But, I cannot ping the
AP1 or the wire PC.
This problem happens during 15 minutes, and after this time period the
connectivity is back.
It seems that it is a problem with an agingtime that blocks the AP from
forwarding traffic.

After putting a sniffer in the laptop and the PC, I could tell that the
traffic is forwarded
by the AP from the wireless to the wire but the traffic from the wire
to the PC is not forwarded
to the wireless. This means that any arp sent by the laptop is seen in
the wire, but any arp reply
is not sent to the Wireless.

Now, the question is why does AP block the traffic only in the wireless
direction.

Duh. It shouldn't do that unless it's blocking all broadcasts.

Try a few experiments. I'll assume Windoze XP SP2 Home.

1. Connect to AP2. Run:
Start -> Run -> cmd <enter>
ARP -d * (flush the entire ARP table)
Now, try to ping everything again.

2. Connect to AP1 as you did in the first case that worked. Ping
everything to be sure it's still working. Run:
ARP -a
and record the results.

Now move to AP2 and run:
ARP -s ip_address 00:aa:bb:cc:dd:ee
for AP1 and the PC exactly as it appeared in the "ARP -a" listing. You
don't need ARP broacasts if you can supply them manually.

If that works, then you've found a nasty bug in the Linksys firmware
(which you didn't specify the version). If it doesn't work, then the
problem is somewhere else, possibly a MAC address filter in the access
point.

Looking at the WAP54GP setup at:
http://www.linksysdata.com/ui/WTR54GS/
I find lots of potential probelems:

1. I notice that it supports RIP (router information protocol). Make
sure this is off as it may cause entertainment value.

2. Make sure you did *NOT* clone the MAC address of the PC or you'll
have identity problems. That works fine with a router, but gets messy
with an access point that doesn't have the WAN-LAN isolation of the
router.

3. This is the first access point I've seen that has a firewall. Turn
it off:
http://www.linksysdata.com/ui/WTR54GS/1.0_15/Security.htm

4. The WAP54GP has a DHCP server. This is my guess as to the most
likely culprit. You should only have ONE DHCP server on a system.
Turn off one of the DHCP servers in either AP1 or AP2.



--
Jeff Liebermann jeffl@xxxxxxxxxxxxxxxxxxxxxx
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
.

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