You run puppet and puppet-server 0.24 or later.

A puppetmaster must be set up to serve at least one environment, but preferably three environments. See also: Section 11.5.1, “Setting Up Environments”

You have domain specific configuration manifests and files in a multi-domain specific or domain specific version controlled tree.

You have the operating system name and version available from facts. In Red Hat and derivative distributions, this requires the redhat-lsb package to be installed.

You are able to use the puppet-module-git and puppet-module-webserver modules from puppetmanaged.org, or you are able to change your modules to make them compatible with the puppet-module-puppet.