In Chapter 2 we talked about the ways that you could define your hosts or nodes to Puppet. We talked about specifying them in a variety of forms as node statements in your Puppet manifest files. We also mentioned that Puppet has the capability to store node information in external sources. This avoids the need to specify large numbers of nodes manually in your manifests files, a solution which is time-consuming and not scalable.
Puppet has two ways to store node information externally:
External Node Classification
LDAP server classification
The first capability is called External Node Classification (ENC). ENC is a script-based integration system that Puppet queries for node data. The script returns classes, ...