I'm having a wireless problem with one of the sites I have to support. Before anyone scolds me about a site survey ;-)
We sort of inherited this setup from the customer when we took over their network and it never really has worked correctly. I'm trying to avoid telling them to hardwire their PCs.
The site is a Manufacturing facility with a corrugated metal roof, 25 ft cielings and large power transformers. There are two access-points that serve the manufacturing floor, one on either side of the building mounted about 10ft off the ground on poles. There's another access-point that serves the lobby and conference room, for a grand total of 3 APs. All three APs are Model: AIR-AP1231G-A-K9 with (I believe, I havent actually been to the site) stock antennas. The APs are all connected to the same switch with the same VLANs (One for Guests [internet only] and one for internal clients).
As for security, the clients authenticate via Certificates that are verified with the Radius Server / Active Directory.
The issue is that clients tend to not stay associated with their AP, they roam from AP to AP. Is there any way to keep clients (Intel Wireless cards for the most part) from roaming to another AP? Is there somthing I can configure on the APs to make them stick? We've tried adjusting power on the APs as well as different antennas (Directional vs omni).
Here's a sample of what we get from the logs:
Aug 24 14:41:54.608: %DOT11-6-ASSOC: Interface Dot11Radio0, Station 0018.391a.abe4 Associated KEY_MGMT[NONE]
Aug 24 14:44:48.438: %DOT11-6-ASSOC: Interface Dot11Radio0, Station 0004.2399.b809 Associated KEY_MGMT[NONE]
Aug 24 15:07:07.773: %DOT11-6-ROAMED: Station 000f.3da9.fa87 Roamed to 0012.0019.9700
Aug 24 15:07:07.773: %DOT11-6-DISASSOC: Interface Dot11Radio0, Deauthenticating Station 000f.3da9.fa87
Aug 24 15:08:08.767: %DOT11-4-MAXRETRIES: Packet to client 0018.391a.abe4 reached max retries, removing the client
Aug 24 15:08:08.767: %DOT11-6-DISASSOC: Interface Dot11Radio0, Deauthenticating Station 0018.391a.abe4 Reason: Previous authentication no longer valid
Aug 24 15:08:12.934: %DOT11-6-ASSOC: Interface Dot11Radio0, Station 0018.391a.abe4 Associated KEY_MGMT[NONE]
To me it looks like interference issues because I'm seeing quite a few output errors on the radios. Any Ideas how I can fix this problem? Thanks!
I'm sure someone is going to smack me for saying it... but since you mentioned 'Intel' I'm immediately wondering if the drivers on your cleint's laptops are up to date. Old Intel drivers are flaky at best.
Also, how are your APs channeled? Are they selecting the least busy channel on their own, or are you setting them manually?
I just dealt with this same problem and environment with a customer last week. The max retries tells me that it's interference, most likely multipath.
I would lower your fragmentation and RTS thresholds to as low as you can go. I've heard you can go as low as 300, but I did 1024 just to be safe. Also, if you can, turn the power down on those AP's as far as you can while maintaining coverage levels. A good hot signal isn't always best in these environements.
The clients are sensing a lot of interference and then jumping to the next AP even though it may have a lower signal. It's signal quality and SNR ratio's that it's really looking for.
Try those things out. I did last week and so far we've been doing much better.
Transferring Crash file from standby:
Login to the Active WLC in HA.
(Cisco Controller) >transfer upload datatype crash
(Cisco Controller) >transfer upload filename <Desired filename>
(Cisco Controller) >transfer up...
This is the start of a display filter cross reference between Wireshark and OmniPeek.
The 1st installment is a table of advanced filters. More filters will be added as time allows.
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I have created a Powershell script to automatically add a Wireless Guest User on Cisco WLCs. (tested on 2500 Series)
The script should be completely self explanatory.
Powershell SNMP Module (Install-Module -Name SNMP)
SNMP Write Access to...