Cisco 7945G on freepbx

I have a small PBX setup at my house. I set this all up just for the experience setting it all up, and of course for the fun of it.

I want to connect a Cisco 7945G to freepbx. It currently has SCCP firmware on it. I have the latest download of the SIP firmware for the 7945G, It’s getting an IP address so uploading to the phone shouldn’t be too much of a hassle. But I need some with with specifics, because I’m a bit of a dummy. I need to, ‘upgrade’ to SIP firmware, and get it to register with Freepbx. Would someone be willing to provide me with assistance on getting this to work? I know these phones will never be perfect with the SIP firmware, but I am just wanting to do this for the experience and so I can help other people with this after I learn my self. Thanks!

These are absolutely the worst phones to learn on. You either need to install SCCP/Skinny on Asterisk (which FreePBX has no direct support for) or you need to flash them to SIP and lose a bunch of standard features because these phones were 100% designed for the Cisco UCM first and general SIP as an after thought. Now you can get a special patch for Asterisk that makes those features work with Asterisk but it’s a 3rd party patch and you have to recompile Asterisk for it. The maintainer of the patch does a good job of keeping it to as current as possible with Asterisk LTS releases (13 and 16).

The next bump in the road with these phones, they do not have a way to configure them directly. They do no have a web GUI management interface. So you just can’t log into the phone and throw in the settings you would like. You need to have a provisioning server (the PBX will suffice) and you need to create the config files for the phone to use and then tell the phone (via the phone interface) where to pull those config files from so you can get the phone programmed.

The Cisco 79XX is a dead line of phones and part of the reason they are so cheap on Ebay and the like. However, that being said someone like @cynjut, who loves these phones, can probably give you the better step by step to making them work one way or the other (SCCP or SIP).

Personally, if you wanted a phone to learn SIP on you were better off getting a low end Polycom, Yealink or something along those lines. A phone that is a SIP phone first and follows the SIP standards vs a phone designed for a specific PBX that doesn’t follow SIP standards (it’s Cisco, they have their own version of things as usual).

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Yeah I know they are absolutely unforgiving, but I’m just really set on them. I want the down and dirty stuff like installing SCCP in asterisk. I also have a 8961 if that is going to be any easier, but I feel like that would be harder. I’ve played around with the SIP phones enough, and I got all the fun out of them.

A step by set for installing SCCP on Asterisk, and uploading the correct configuration would be awesome.

I set up a very similar phone, the 7965G, just a couple months ago by following through the documentation at

It’s really best if you start there and then if you have specific questions, come ask them here if relevant to FreePBX. The process is too much for someone to write out here a step-by-step, especially since the chan-sccp folks have already done a great job.

Thanks i’ll check it out

I cut my FREEPBX teeth using Cisco’s 7940’s mainly because as @BlazeStudios says, they are cheap and I wasn’t going to spend too much at that end of the learning curve.
It was difficult to get them going, I did brick a few too!! The information is out there, that’s where I got it and they worked perfectly well in my business and now are in a box in the basement as I’ve upgraded to SIP and don’t regret them as a learning tool albeit pulling what little hair I have out. I agree with Tom, you’ll save time and a divorce if you go with SIP devices.

This isn’t actually true. The Chan-SCCP-B module is installable and requires minimal “extra” steps: you need to install the asterisk-devel YUM update and you need to compile Chan-SCCP-B against that. Once done, you “not load” the chan-skinny Asterisk module and “load” the chan-sccp module.

There is also a “constantly in development” FreePBX management pageset for the phones in Skinny mode that allows you to manage them from FreePBX. I’ve written in this group extensively about both of these options.

The 79xx phones in SIP mode are terrible. In Skinny mode, they are actually reasonably easy to use. In addition, because of the way they are maintained, you can update the phones button configuration without having to reboot the phone.

Having said that, I would never recommend these phones to a first-time phone installer. If you have experience and understand the vernacular, however, these phones with Chan-SCCP-B and the FreePBX second-party SCCP Manager, the phones are easier to install than (say) Polycoms being flashed to Firmware version 3 to version 4.

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