There is one application called "WLC Config analyzer". You save your "show run-config" from your WLC in a text file and import it by this application. it will analyze the file for you and tell you what recommendations for voice are missing so you improve them.
When importing a config file you choose what voice clinets you are using, so you need to choose cisco 7921 to it tells you what config improvemetns is needed based on 7921 needs.
BTW, how many voice/data clients are connected to one AP in that area? if I remember correctly if you are utilizing voice then the max number of clients connected to one AP should not exceed 17. If you have more than this number per AP try to minimize the number of users concurrently connected to the AP then try again.
Hope you'll find the config analyzer useful.
If useful please don't forget to rate.
Rating useful replies is more useful than saying "Thank you"
I do recall a discussion about a year ago. The OP described signal issues with the 7921G after it was dropped on the floor. The OP opened up the unit and discovered that the antenna got dislodged from the connectors.
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...