This is a HOW TO upgrade guide for Converting a Cisco IP Phone 7975 from SCCP (Skinny Call Control Protocol) to SIP Firmware.
Step 1: Obtain the Firmware files
Download the Cisco 7975 SIP Firmware files. The most stable and recommended Cisco 7975 firmware version is SIP75.9-4-2SR3-1S. Extract the .zip package to a folder on your computer.
Step 2: Prepare a TFTP Server to deploy the firmware files to the phone
Download any TFTP* server software. The one that was used in this specific SIP upgrade is called Pumpkin, but you can use any TFTP software.
Install the TFTP server. Specify the location where where you have extracted the .zip package. Configure the TFTP server so that Read Request Behaviour is set to “Give all Files” without “Prompt before giving file”. This way you make sure that the read request of the phone happens without any complications.
* The Trivial File Transfer Protocol (TFTP) is normally used only for booting diskless workstations. The TFTP server package provides the server for TFTP, which allows users to transfer files to and from a remote machine.
Step 3: Create and place the necessary Cisco configuration files
Place the apps75.9-4-2ES26.sbn, cnu75.9-4-2ES26.sbn, cvm75sip.9-4-2ES26.sbn, dialplan.xml, dsp75.9-4-2ES26.sbn, jar75sip.9-4-2ES26.sbn, SEP[MAC].cnf.xml, SIP75.9-4-2SR3-1S.loads, term75.default.loads and XMLDefault.cnf.xml files you extracted from the .zip file in the TFTP server root directory, the one you defined on the TFTP server options, e.g. C:\provisioning.
Locate the file named SIP[Mac].cnf extracted from the .zip - This file is for the configuration of the phone. ***Rename this file and put the MAC Address for your SIP phone in place of [mac]***. The MAC address must be specified in capital letters, you can locate the MAC address on the back of the phone at the very bottom. E.g. If my Cisco's MAC address is 00:0a:95:9d:68:16, I would rename the file SIP000A959D6816.cnf.
Place the file in the TFTP server root directory, the one you defined on the TFTP server options located above, e.g. C:\provisioning.
Step 4: Upgrading the Cisco Phone
**PLEASE DO NOT UNPLUG THE PHONE AT ANY COST WHILE UPGRADING. IT WILL BRICK YOUR PHONE.**
Configure the phone to pull files from our TFTP Server:
- Press the Settings button on your telephone.
- Dial **# on your phones keypad to unlock the settings menu.
- Press 2 on your telephones keypad to enter the Network Configuration menu.
- Press 1 to enter the IPv4 Configuration Menu, otherwise press 2 to enter the IPv6 Configuration Menu.
- Press 16 on your telephones keypad to jump to the Alternate TFTP setting, press the Yes softkey to change the current setting from No to Yes.
- Press 17 on your telephones keypad to jump to the TFTP Server 1 setting, press the Edit softkey and enter the IPv4 address of your TFTP server. Press the Validate softkey, followed by the Save softkey to save the changes.
- Press 8 on your telephones keypad to jump to the IPv6 Alternate TFTP setting, press the Yes softkey to change the current setting from No to Yes.
- Press 9 on your telephones keypad to jump to the IPv6 TFTP Server 1 setting, press the Edit softkey and enter the IPv6 address of your TFTP server. Press the Validate softkey, followed by the Save softkey to save the changes.
- Reboot your phone!
Usually after you press ‘Save‘ it will reboot the phone, if it does not in one minute, go ahead and manually reboot it by unplugging it from the power source. The phone will now start communicating with our TFTP Server and get the firmware. You will see that status on the phone. It will verify the load and start uploading it on the phone. While it is uploading, if you look at your TFTP Server and go to Log viewer tab, you will see the events occurring and what file the phone is trying to get.
Once the phone has succesfully pulled all the files from the TFTP server and rebooted, press the Settings button followed by 6 and 3 on your telephones keypad, you should now be in the Firmware Versions menu. The Load File option should display SIP75.9-4-2SR3-1S, if it does, you were successful in converting your Cisco IP Phone. Congratulations!!
NOTE: Please be aware that although these phones do have a web interface. The only way to configure or give configuration updates is via Configuration files using TFTP.