[c-nsp] Zero MAC affecting comms through aironets

[Graham Hausler]

I hope this is an appropriate posting here.

I am having difficulty understanding behaviour I am currently seeing 
between Cisco 1310 aironets (configured as workgroup bridges) and Cisco 
1240 access points.
Every time a bridge associates/re-associates, a client, having that bridge 
as its parent, is shown in the access point associations status. This 
client has a zero MAC address (0000.0000.0000).  When another bridge 
associates, this zero MAC client's parent moves to newly associated 
bridge. What is this behaviour about?

I believe as a consequence I am seeing funny comms behaviour, whereby the 
TCP/IP/ping communications through the bridge to the access point LAN is 
only successful if the bridge has this "0000.0000.0000" client as one of 
its children. Essentially pings through the first associated brdige stop 
once a second bridge associates. If a re-authentication is set up for the 
first brdige, then the ping starts to succeed again once the 
re-authentication occurs (and this zero MAC client is back with the first 
bridge). If I disassociate the second bridge, including the zero MAC 
client, before the first bridge reassociates, then I never see the pings 
restart!

The relevent configurations are
Cisco 1310, IOS 12.3(7)JA2, configured as workgroup bridge using 
"CKIP+CMIC" encryption and LEAP authenitication.
Cisco 1242, IOS 12.3(7)JA2, configured as access point using "CKIP+CMIC" 
encryption and LEAP authenitication (have tried with both local and Funk 
Radius servers).

Any insight into the above behaviour would be gratefully received.


Cheers
Graham

ERG Transit Systems
247 Balcatta Road Balcatta WA 6021 Australia
Tel: +61 8 9273 1253 Fax: +61 8 9273 1535
Email: ghausler at erggroup.com Website: www.erggroup.com