the first time i build a icinga monitoring for a vsphere environment. before i configured only checks for esxi machines directly. love the check_esx3.pl module from op5.com. some pics from pnp4nagios:
got the system running on a debian squeeze, all packages from the main,nonfree,controb repositories. pnp4nagios is backported. so all packages are covered with security updates and the normal apt super cow power !