Is there a difference whether you use 40 or 128 bit WEP, or EAP, or LEAP?
Could it be that the units are associating, but some (more than 6 or 12) are not getting DHCP addresses?
Maybe try a "debug dot11 aaa" to see what the authentication traffic is looking like ("no debug dot11 aaa" to turn it off).
Verify the associations with "show dot11 associations" and see if perhaps the clients are associating with the AP (as far as the AP is concerned), but the client (for whatever reason) doesn't know it has associated).
Maybe put on a packet analyzer (like Ethereal) on the 7th/13th PC and capture the association (or lack of)to see where the sequence is failing. If the PCs associate, then start blabbing (i.e., consuming a lot of bandwidth) it might just be a lack of available bandwidth. If this is the case, you may get a little relief by lighting up a few VLANs.
There's maybe some additional stuff, give this stuff a try and we can take it from there.
I did some debugging, but unfortunately I had already increased the max-associations and had fixed the problem.
I cannot prove it, but I have a feeling that perhaps the associations slots take a while to time-out so we were exhausting them when we had it set as low as 30.
I have set the max-associations to the default (255) - and I do not feel this is less secure as we are handling the association using PEAP available in AD 2003 and clients cannot associate unless they are AD members within the correct groups and have the correct settings.
The problem now no longer exists, but I will continue to monitor.
Transferring Crash file from standby: Login to the Active WLC in HA.
From CLI: (Cisco Controller) >transfer upload datatype crash (Cisco
Controller) >transfer upload filename (Cisco
Controller) >transfer upload mode tftp (Cisco Controller) >transfer
This is the start of a display filter cross reference between Wireshark
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