Upgrading to Puppet 4

Let's first look at how users of the older Puppet 3 series can approach the update.

Tip

Instead of upgrading your Puppet Master machine, consider setting up a new server in parallel and migrating the service carefully. This has some advantages. For example, rolling back in case of problems is quite easy.

The new Puppet 4 version can be installed in several ways:

1. Using the Puppet Labs repositories, which will remove older Puppet packages:

   This method means a hard cut without testing in advance, which is not recommended. The update to Puppet 4 should only take place after in-depth testing of your Puppet manifest code.

2. Installing as the Ruby gem extension or from tarball

   This approach requires a separate Ruby 2.1 installation, which is not available on most modern Linux distributions.

3. Update to Puppet 3.8, enable and migrate to the environment path settings, and enable the future parser only on a special testing environment:

   The latter solution is the smartest and most backward...