Just wanted to throw this out there for anyone looking on setting up TFTP for older phones like Cisco 79xx series. Just a note - all commands are in italics. Things you will want to have handy. WinSCP and Putty. I used WinSCP to find the provisioning instance folder which is located in /var/lib/3cxpbx/Instance1/Http/Interface/provisioning/ Open the provisioning XXXXXXX and use WinSCP to transfer the Cisco files. If you don't have them you can find them here. Just a little note, don't copy the folder and contents to the directory, just the contents. Use Putty to ssh to your PBX or terminal if you are on a Mac. Once connected you will need to install a TFTP server. For this I used tftp-hpa. To install type: sudo apt-get install tftpd-hpa Your TFTP server is now installed. Now we need to edit the config file. You can use vi or nano, I prefer nano to edit. sudo nano /etc/default/tftpd-hpa Edit the config file to reflect your provisioning directory. Don't forget the start and end quotes! TFTP_USERNAME="tftp" TFTP_DIRECTORY="/var/lib/3cxpbx/Instance1/Data/Http/Interface/provisioning/XXXXXXXX" TFTP_ADDRESS="0.0.0.0:69" TFTP_OPTIONS="--secure" Write and exit Nano (use ctrl+O to write and ctrl+X to exit) Now we need to make our changes active. Type these commands: service tftp-hpa stop service tftp-hpa start And that is all it takes to setup TFTP on your 3CX Debian server.