Moving 7925 phones from AirOS to Catalyst controllers

[Wes Schochet]

Hi All-

I am continuing my journey to migrate controllers from 5520s (8.5.164) to 9800s (17.3.3).

I have a large fleet of 7925s wireless phones. They have trouble connecting via the new controller.  They use the same subnet.  Other clients on this SSID seem to operate normally.

The 7925s struggle, but do eventually connect using PSK authentication. 

However, they will not make or take calls saying "Network Busy" in the display.   From what I have been able to find, this may be a CAC issue, but I can not find any details. 

I have done my best to translate the SSID and profile settings from one platform to another. 

I am using 802.11a only. 

The RF profile has 6 and 9 Mbs disabled, 12 Mandatory and all others supported.

Using central switching, central authentication, central DHCP and central association.

I did follow the best practices in this doc Configure a WLAN for Voice with Cisco 8821 on Catalyst 9800 WLC .  It did not resolve my issue!

I attached a debug for good measure.  Any ideas or input would be appreciated!

Wes

[Haydn Andrews]

First thing im guessing you have configured the mobility between the controllers given your running the IRCM image on the 5520.

Couple of things to check:

Check 802.11k/v/r are the same on aireOS to IOS XE for the SSID

There is a good guide here for best practices with the 8821 handset but most of them should still be relevant to the 7925 handsets.

https://www.cisco.com/c/en/us/support/docs/wireless/catalyst-9800-series-wireless-controllers/214863-voice-deployment-on-catalyst-9800-wirele.html#anc15 

TAC is also recommending 17.3.4C now so there might be some bugs fixed in the upgrade.

[Wes Schochet · Accepted solution]

I just wanted to follow up on this after opening a TAC case to resolve the issue:

Apparently, Call Admission Control CAC is "broken" on the 9800s. To get the 7925 to function properly, I had to turn it off all together.  To disable CAC, which is now called ACM:

Shut down the radio under Configuration -> Radio Configuration -> Network 
Turn off ACM under Configuration -> Radio Configuration -> Media Parametrers (Voice):
Remember to un-shut the radio!

In the policy profile under Configuration -> Tags & Profiles -> Policy (QOS Tab):
Set AutoQOS to none
Set QOS policy to platinum for voice

I assume that the newer wireless phones like the 8821 work as designed?  I don't have one handy to test.