not a newbie but, In a Large Enterprise Facility several Cisco 7921/7925 mobile ip Phones fails to register for ip addresses

[barry_scott]

                   All,

We would appreciate any tips .  The Configuration/syntax is correct for the mobiles phones.  

The process is as such

-DHCP request process an option 150 to a TFTP Server to download it's config file to complete registration

-Once a ip Phone fails apparently tries the next Server ip address available in an endless loop

I seen a community member mention:

per Cisco Technical support we need to upgrade to 7.0235.0.(recommendation)

There is an open issue in 7.0.230.0 in regards to broadcast key rotation.

I am not sure what version of Call Manager we have.

ME: From studying Cisco devices wireless, connected, remote devices, send ACK always up transmissions back and forth to let each other know I'M GOOD. Submission ACK values around 2ms.

[Amjad Abdullah]

Barry,

Plz clarify more.
DHCP fails? Or the TFTP request is failing?
What is the security configured for your voice WLAN?
Do the phones connect correctly to an open SSID (no security) on same vlan of your current SSID?

Regards,

Amjad

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[barry_scott]

Amjad,

I believe the DHCP is not the issue here.  I asked a our Telecom Engineer and Network Engineer and there was not mention of running out of ip addresses.  So i am led beleive the DHCP scope for DATA/VOICE ips are enough.  According to the Cisco ip phone boot process this would me more of a TFTP related issue(I guess). The phones connect from looks of with no security to a secure SSID of course to the same VLAN.  According the Cisco ip phone boot process dhcp option 150 directs the ip phones to the TFTP server to download it's XML configuration file and the ip phone attempts to contact the call processing server  listed in the config file to complete registration and at this point if it fails to do so and the phone looks for the next available server mentioned in the configuration file.  The Telecom engineer said there is several ip's in each phones config file(i hope?). 

Let me mention I have no access.  So I have to ask the guys why is this happening?? 

I am led to believe the phones are not receiving the device to device ACK/SYN: timely enough I believe the default transmisssions suppose to be 2ms,?  Or maybe file corruption on CiscoCall mgr or CUCM?  My notes also mention if the ip phone is not configured in CCM/CUCM of course it doesnt exist on the server so ip phone will request it unless auto-reg is off or on hmmm? Auto-Registration feature this could be an issue??? If it's not on?? Not sure 

[Amjad Abdullah]

Barry: note please most of the concerns you have are related to the voice scope, not to the wireless scope.
You need to make sure the handsets are getting a DHCP ips from the correct scope and they receive correct option 150. Make sure your phone handsets are successfully added to the call manager.

If you still have issues with the IPs or joining the phone to the call managerI suggest moving your discussion to the voice forums. This forum to handle phone issues from wireless perspective.

HTH

AmjD

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