Working with Asterisk a lot recently at work, I made this kickstart file for CentOS 5.5 32-bit to automatically install the OS, install Asterisk, update the OS, and reboot. Upon first boot you’ll have a fully up to date server with Asterisk already up and running with sample config files and a small selection of music on hold files installed. You’ll still need to add rules to IPTables for sip ports 5060 and 5061. Get the kickstart file from Pastie here.