Link: How to Install Asterisk 11 in RHEL/CentOS/Fedora and Ubuntu/Debian/Linux Mint

Asterisk is an Open Source software PBX (Private Branch Exchange), developed by Mark Specer of Digium. It allows you to make calls to one another which may have connected to other PSTN (Public Switched Telephone Network) and Voice over Internet Protocol (VoIP). Asterisk runs on Linux, BSD, MacOSX and others. Having built-in features like voicemail, conferencing, IVR, queuing etc.

In this article, we are going to see a basic installation and working of Asterisk 11 in RHEL 6.4/6.3/6.2/6.1/6.0, CentOS 6.4/6.3/6.2/6.1/6.0, Fedora 18,17,16, Ubuntu 12.10/12.04/11.10, Linux Mint 14/13 and Debian Linux Operating Systems.

How to Install Asterisk 11 in RHEL/CentOS/Fedora and Ubuntu/Debian/Linux Mint (TecMint.com)

Link + notes: Configuration of APC UPS in Ubuntu

The APC PowerChute utility will only run in Windows, but if you are running Ubuntu Linux (or some variation thereof) you can have pretty much the same thing by following the instructions in this article:

Configuration of APC UPS in Ubuntu (Tech-Niche)

The article suggests you install gapcmon but you probably don’t need to do that, because Ubuntu already includes a Power Statistics utility that works well enough for most users.

If you have problems getting it to work, make sure the USB cable is plugged into the correct jack on the UPS (with some models it’s easy to plug it into a network cable jack by mistake). From the command prompt issue the command lsusb and it will tell you what is connected to your USB ports — you should see an entry for “American Power Conversion Uninterruptible Power Supply” if the cable is correctly connected.