Review: Puppet 3.0 pulls more strings

Working with Puppet requires learning Puppet's configuration language and knowing your way around Puppet's classes and modules, which are organized in configuration files in a specific hierarchy under /etc/puppetlabs/puppet. Without going into the heavy details, you can consider all modules to be includes in a big script, with classes defined and linked to specific server nodes or groups of nodes. This provides a very straightforward method of dealing with the complex and detailed requirements of managing multiple server platforms and distributions, not to mention switching and storage applications.

The Web UI included with Puppet Enterprise is well appointed and straightforward, allowing for the creation and management of nodes, groups, and classes, as well as report generation and viewing. It is a useful tool for manipulating node organization and quickly determining issues with certain parts of the framework. It also provides limited Live Management of nodes or groups of nodes. However, for many implementations it may be easier to think of the UI as read-only, and to work mostly through the command line. The deeper into Puppet you get, the more likely this will become, as you may discover that you can only apply certain configurations and modules to nodes and groups through the CLI, and these changes may not be reflected in the Web UI.

An example might be a module downloaded through the Puppet Forge module-sharing site that cannot use a class due to the nature of what it's configuring. In this case, you will need to apply the module to nodes or groups from within the Puppet configuration files, as you can't define a class that maps to a class definition within the Web UI. This configuration element will thus not appear in the Web UI.

I also encountered a few bugs in the Web UI, such as the fact that you can add a group with a name containing a period, but you cannot thereafter edit or delete that group through the UI. This would seem to be an input validation bug, because it appears that a period is an illegal character in group names.

Standing up the Puppet
Installing Puppet is conceptually very simple. Choose a supported platform for your Puppet Master server, and run the install script. This will prompt for a variety of packages and options to be installed: the Puppet Master, PostgreSQL, Cloud Provisioner, and so forth. The install script will also prompt for a username and password for the first administrator in the Web UI.

It's all very simple, but somewhat lacking in error checking and error reporting. For instance, if you install on a Linux system that has PostgreSQL already installed but not configured or running, the installer will happily install its own PostgreSQL binaries -- then try to use the wrong client to connect, which will fail, and produce a fairly useless error message saying that the PostgreSQL server failed to start, even though the server was clearly running. Fortunately after some digging, that root cause was discovered and fixed, but it wasn't the only time the installer bailed without any useful logging or apparent cause. The installation scripts are simple bash scripts, so debugging wasn't a big challenge.