I got a Cisco 7945G off eBay. This is a phone which was $400 when new but can now be picked up for about $16. These phones went End Of Sale in Jun 2018, working perfectly. A testament to the good build quality of these phones, and perhaps the previous owner’s careful handling.


Since these devices are no longer supported many companies will be getting rid of them (or probably already have) so there should be some bargains to be had for phone geeks.

Q: Does the Cisco 7945G work with Asterisk?
A: Yes. You need to load the SIP firmware (the focus of this post) or chan-sccp (out of scope for this post but I’ll check it out at some point).

Q: Does the Cisco 7945G work with SIP?
A: Yes. You need to flash the correct firmware though.

Q: Is it really hard to get working?
A: No. If you’re comfortable with Linux and a few command line tools. And assuming you already have Asterisk set up.

Q: Is a lot of the information on the web about how to set up the 7945G wrong?
A: Yes. There is a lot of confusion about config files (the 7940 and 7941 use different ones).

Q: Will you tell us how you got your phone to work?
A: Yes! However – this is what works for me. You will need to tweak the config in places.