We have 2 Aironet 340 bridges that have been working flawlessly for 18 months. During the last 3 weeks they started dropping connections periodically throughout the day while users were working I checked out the radio error logs and they are reporting large (100-3000) volumes of Receive CRC errors and large numbers of Transmit Retries and Holdoffs over a short period of time 3-4 minutes.
I found a document on CCO that states CRC errors could be caused by radio interference but to check the Line-of-Sight first. I checked the line of sight and the path appears very clear.
The Radio signal strength meter is around 90% with quality around 50-60%.
We have installed more bridges within the last month. All bridges Frequency setting was set to "auto". I discovered one pair was using the same requency as another pair so I turned off "auto" and set the frequencies manually.
Still large numbers of CRC, Tx Retries and Holdoffs. However the connectivity issues seem to have been fixed.
My question is are these large numbers normal, I don't remember seeing them in the past and if not what should I check?
Most people check the unused frequencies at the 'root' site, but forget that when the other radio attaches to it, there may be a frequency problem near that end that is not appearant at the root.. I would use the site survey function on each radio and find the best frequency for both ends. Then set that frequency manually.
Of course, as someone else pointed out, water in your waveguide could cause similar problems. This is hard to troubleshoot without replacing your cable (and don't think you can dry out your cable... water wicks its way down/up the cable). WATERPROOF...WATERPROOF...WATERPROOF!!!
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.
It is a living doc, so check back for changes every so often
Please feel ...
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...