Disable the mandantory of "reconfigure-accept" option on CNR7 DHCPv6 server

[marco.peng]

Hi People

I was trying to let Windows 7 get IPv6 address from CNR7 DHCPv6 server but cannot get it done.
Afterwith, I read the cnr log and capture the DHCPv6 packtes to find why.
I got some info about this issue, no option-20 existed in those DHCPv6 solicit messages and cnr log told: no required reconfigure-accept option, so drop it.
Can anyone help on this issue? How can I change the CNR setting to disable the mandantory?

Thanks!
Marco.

[Nael Mohammad]

Post your cnr_tactool so we can review the logs and settings.

[marco.peng]

Please find attached zip and help review it.

[Nael Mohammad]

-nael: removing attachment for security reasons as it contains information about your CM environment but I have downloaded and will review it.

[Nael Mohammad]

Can you tell me a little more about your CM environment?  It seems an option is missing in the policy associated that the CM expects. Please enable the debugs from the cnr nrcmd cli by doing a "dhcp setDebug VX=1" and duplicate the problem.  Get all the name_dhcp_log.xxx and post them. Afterwards disable the debugs by doing a   "dhcp setdebug VX=0" to disable the debugging.

Are you using BAC in your setup?

[marco.peng]

No BAC in my enviroment.

This DHCPv6 issue is not for CM, it's come from CPE behind a operational bridge CM.

I have attached new zip file for you, in the zip, you can see that a same CPE cannot get IPv6 addr from CNR7 but can do it from my Dibbler server.

Sure, the DHCPv6 solicit messages will be replyed by CMTS.

I  guess the missing of opt-20 is the key.

Thanks for your quick support!

Marco.

[marco.peng]

a quick question, why I got below output when I attempt to disable the debbugin?

nrcmd> dhcp setDebug VX=0
316 Invalid - dhcp setDebug VX=0

[Nael Mohammad]

To disable the debugs, you need to type "dhcp unsetDebug" and do a "dhcp reload".

For setting options, follow the steps in the documentation:

http://www.cisco.com/en/US/partner/docs/net_mgmt/network_registrar/7.1/user/guide/UG25_IP6.html#wp1083841

With CNR 7, there is a bug CSCtd04253 which might be impacting the ability to reconfigure the clients. The solution is download and install the latest version of CNR 7.1.x.

http://www.cisco.com/cisco/software/release.html?mdfid=281136482&flowid=4969&softwareid=282759027&release=7.1.2.1&rellifecycle=&relind=AVAILABLE&reltype=latest

http://tools.cisco.com/Support/BugToolKit/search/getBugDetails.do?method=fetchBugDetails&bugId=CSCtd04254

You can force the server to send the specific option by including the options in the v6-reply-options. For your issue, you need to do the following with the V6 related policy:

"policy set v6-reply-options=20" from the nrcmd, save it, and do a "dhcp reload".

In the policy for the client that CM is in, you need to set the "reconfigure" attribute. It's defaulted to allow.

[marco.peng]

why force server to send out opt-20? the cpe does not want this.
the point is cnr7 always wants cpe's solicit message having opt-20, we need to remove the dependency.