An OS template is basically a set of packages from some Linux distribution used to populate a container. With OpenVZ, different distributions can co-exist on the same hardware box, so multiple OS templates are available. An OS template cache is an OS template installed into a container and then packed into a gzipped tarball. Using such a cache, a new container can be created in a matter of minutes, if not seconds. For information about templates and installation instructions, see [1]wiki:OS template cache preparation. Utilities Template utilities is a software aimed at template maintenance, such as creation and update of templates and continers. Currently these consists of vzpkg, vzyum and several versions of RPM utility repackaged for OpenVZ. Metadata Template metadata is data needed to (re)create template cache. Metadata for a template contains the following information: list of packages that form this template; locations of package repositories; scripts needed to be executed on various stages of template installation; public GPG key(s) needed to check signatures of packages; additional OpenVZ-specific packages. Precreated An OS template cache is an OS template installed into a container and then packed into a gzipped tarball. Using such a cache, a new container can be created in a matter of minutes, if not seconds. References 1. http://wiki.openvz.org/OS_template_cache_preparation