What is the default node name for Puppet agents?

The default node name for Puppet agents is referred to as "certname." This designation refers specifically to the common name for the SSL certificate that is associated with the agent. The 'certname' is typically derived from the hostname of the machine on which the Puppet agent runs, but it can be explicitly set in the Puppet configuration files.

When Puppet agents communicate with the Puppet master, they use their certname to identify themselves securely. The certname must be a unique identifier within the Puppet ecosystem. This ensures that every agent connection can be authenticated and authorized based on its certname.

The 'hostname' generally refers to the system's network name but may not account for differences in how Puppet identifies nodes versus how they are named in the operating system. Similarly, 'hostcert' is a term associated with the SSL certificate itself that is used for secure communications but does not specifically define the name used in Puppet. The 'node_name' parameter, while it might sound relevant, is more about how agents can configure their names but does not directly describe the default setting itself.

Thus, understanding that the certname serves as a unique identifier based on the SSL certificate establishes its importance and correctness as the answer to this question.