FreePBX is an open-source web-based GUI for Asterisk (PBX), a voice over IP server. On-topic questions include those about writing FreePBX modules, or extending built-in dialplan. Stack Overflow is not an appropriate place for server management or general support of either FreePBX or Asterisk.
FreePBX allows easy management of the Asterisk PBX and automates the creation of complex applications such as IVRs and conferencing systems, as well as management of user extensions and features. It is comprised of various modules which can be independently installed or uninstalled, and an API is provided for third parties to create their own modules.
FreePBX also provides a Linux distribution based on Red Hat Enterprise Linux 7.0, which provides a pre-installed version of FreePBX that is able to run commercially licensed modules.