Changing IP of Freepbx server

Hi chaps

We have to change our IP range from 192.168.1.x to 192.168.16.x here.

I’ve done some tests and the servers and phones change their IPs but the phones dont register. When we look at the account settings on the phones their SIP server is set to (the old ip of freepbx) and the TFTP server is set to the same. This IP has now changed to

I’ve tried rebuilding the configs on the freepbx server for all the phones but that didnt result in them changing their SIP server settings or tftp settings. I’m guessing thats because the TFTP IP on the phones is already wrong.

I have hundreds of phones to change. Is it possible to do this automatically some how? One option is to factory reset the phones but I’m aware that users have made changes to things and I’d rather have that as a last resort option.


Without specific information as to what type of phones you are using its pretty hard to assist you, as not all phone vendors deal with tftp provisioning in exactly the same fashion.

That said, you need to look at several things one of which might help.

  • Your DHCP server - there is an option code, sometimes 66, sometimes something else, that specifies the IP or the URL of the provisioning server. Make sure this has been updated, and pointing where you expect. This is usually the first place the phone gets information on what to connect to.
  • Your DNS server - some phones may be looking for SRV type records in your DNS, these must point to the correct IP.
  • There may be a "master" config file for your phones in the /tftpboot directory (again, varies by vendor). In this file, assuming the phones get to the server via the DHCP option, may be told contradictory information in master configuration file. Check this file to make sure the IP has been updated.
  • There may be per-phone config files in your /tftpboot directory that contain the old IP address of the server, make sure these are also updated.

Good luck!


What sort of phones do you have? As already mentioned it’s difficult to provide answers without knowing the details. You use DHCP option 66 (some manufacturers used to use option 43 as well) to change the TFTP server. But also some manufacturers have this switched off by default on phones so unless it’s switched on (maybe check a few sample phones) it’s not going to work. You could always setup a tftp server on the old address and offer some config files on there to change the IP address of the TFTP server and see if that works.

With 100’s of phones to convert you may want to consider bringing a consultant on board that has experience with conversions of this size and larger (ask for references).

There are many things that can be done to make this completely seamless to your users.

my guess would be option66 has not been updated on the dhcp server. The phones are trying to provision using the old address, and therefore are not being updated with new config.

If you use endpoint manager be sure that you updated the global config with the new ip i had the same problem when i imported my old config on a new server with a different IP. And like everyone else said dont forget to update your dhcp

Thanks bombeur. The Kudos points go to you. It was the global config. Option 66 was correctly set, and I think the phones (Yealink) were getting the config, but the config was pointing them in the wrong place.