Zero config issue from UCM 6208, phones fail provisioning, looking for login/password


I am having a very weird issue off a UCM6208. I have templates set up in Zero Config for 2135, 2170, 2140 phones as well as the DECT DP752. The DP752 devices are connected via OpenVPN and are offsite. They seem to be picking up their settings just fine when you tell the phones to provision. Devices on the local LAN see the UCM and, in fact, pick up the correct config path when you manually kick off provisioning in Zero Config. But then the phones display the username/password prompt on the LCD and stop any further processing.

I have other 6204’s and 6202’s running happily and provisioning via Zero Config with no issue. Not sure what is happening here. In all cases I am setting an explicit admin password in the Zero Config settings. I have tried factory reset of the phones, I have also explicitly set the admin password on the phones to match what I am setting in Zero Config … no luck.

All UCM’s running the latest firmware, The 6208 has locked up once or twice requiring a hard power reset, not sure if that might have something to do with the issue.

Any and all ideas gratefully accepted!


I hope I can help you,
it is normal that Zero Config works correctly locally, via “VPN” the broadcast is not sent, otherwise it would generate huge traffic.
So I think it’s normal that Zero Config outside the local network does not work properly, but not for lack of UCM.


Thanks for your response. You misread my post … Zero Config is failing on the LOCAL LAN.


Did you add subnet in zeroconfig white list (last one) ? By default UCM only allow it is own local subnet.


Thanks for your reply! Yes, in the whitelist. As I said, I have set up multiple UCM’s, only this one is giving me grief.


Well, folks, I figured it out and the clue actually came from Marcin. While I had everything correct in the UCM I had NOT pulled the DHCP 66 option that was in place for my old FusionPBX system. So, it looks like the phone started pulling info from the UCM and then switched over and tried to pull the rest of its config from the old FusionPBX box once the DHCP 66 option had been read. Weird! But everything worked as advertised as soon as I pulled the option 66 info from the DHCP server.

Guess it never hurts to have an additional person look at your configs. Thanks for all the help!