when i’ve upgraded - now the IVR for some reason stopped working… bizzare 
how about more details.
a Distro build? If so who’s? If not what OS and version of asterisk?
it seems that the upgrade for some reason overwrote my sip.conf file (and my previous values for externip and localnet have dissapeared)…
* Your Linux Distribution: (CentOS release 4.5 (Final))
* Your FreePBX version: (2.3.1)
* Your Kernel version: (Linux 2.6.9-55.0.9.EL #1 Thu Sep 27 18:10:45 EDT 2007 i686 i686 i386 GNU/Linux)there is a reason why there are so many #includes with the sip.conf distributed with FreePBX. It is for you to use them vs. using the one that FreePBX ‘owns’ and that you should not modify. So use the #include ones that have _custom as part of them (and the sip_nat.conf if you want which is a bit legacy in its naming structure but is there for you to put settings like externip.
Philippe Lindheimer - FreePBX Project Lead
http//freepbx.org - IRC #freepbx
so how do i know which files are safe in freepbx to modify? thanks
Only the files that end in _custom.conf. They will not exist unless you create them but once created freepbx NEVER touches them and loads them early enough in each of the base configs for it’s settings to take place.
in /etc/asterisk:
globals_custom.conf
extensions_custom.conf
features_general_custom.conf
iax_general_custom.conf
iax_registrations_custom.conf
iax_custom.conf
manager_custom.conf
musiconhold_custom.conf
queues_custom.conf
queues_post_custom.conf
sip_general_custom.conf
sip_registrations_custom.conf
sip_custom.conf
There are several other locations like panel that do the same thing op_buttons_custom.cfg for one. So look at the base file and if you see a include xxx_custom* line edit that file instead of the base.