9971 and option 125 and other messages in dhcpd packets sent from phone

[Jason Aarons]

I can't find anything documented about these dhcp packets the 9971 phones are sending out.  Anyone provide a URL?  Is there a way to turn them off on the 9971?  Running CUCM 9.1.1 and 9971 SIP load 9-4-1-9.

2911#debug ip dhcp server packets

Apr 23 20:48:43.004: DHCPD: client's VPN is .
Apr 23 20:48:43.004: DHCPD: No option 125

[siddharthacharya]

Hi Jason,

Option 125 is used for vendor specific information to get the following:

•  Pilot number (also called primary or contract number), there is only one pilot number in DHCPACK, and REGISTER is done only for the pilot number
•  Additional numbers, or secondary numbers, are in DHCPACK; there is no REGISTER for additional numbers
• SIP domain name

Here is the link for more info:

http://www.cisco.com/en/US/docs/ios-xml/ios/voice/cube_sip/configuration/15-2mt/voi-sip-param-dhcp.html

Not sure if you can disable them or not. You might want to check the phone specific information on call manager.

Sid