Thursday, May 26, 2011

Bring your dead Cisco IP phone back to live

I have an old post talking about how to factory reset your Cisco IP phone:

However in a lot of cases, after you entering the 3491672850*# sequences twice, you phone looks dead.  The right topmost line key will have a orange flash then the screen is dark.  In this scenario you need to:

1. Make sure you have DHCP server configured and your phone can get an IP address
2. Make sure you have option 150 ip configured so that the IP phone knows where to get the firmware
3. Finally, you need to change your switchport to "speed 100" manually!!!!!  I have four phones recovered from "seems dead" state and it seems to be the trick.

After you make sure you have done the 3 steps above, restart the factory reset steps and you can recover your dead phone!


Ing.Aguilar said...

have option 150? what is that?

Panda eats bamboo said...

Option 150 is the DHCP option to let your client knows what is the TFTP address. In the UC world it usually is your UCM address. It can be multiple addresses, depends on how many subscriber you have.

dokan sam said...
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