Logging debug messages

It can be very helpful when debugging problems if you can print out information at a certain point in the manifest. This is a good way to tell, for example, if a variable isn't defined or has an unexpected value. Sometimes it's useful just to know that a particular piece of code has been run. Puppet's notify resource lets you print out such messages.

How to do it…

Define a notify resource in your manifest at the point you want to investigate:

notify { 'Got this far!': }

How it works…

When this resource is applied Puppet will print out the message:

notice: Got this far!

There's more…

If you're the kind of brave soul who likes experimenting, and I hope you are, you'll probably find yourself using debug messages a lot to figure out why your code doesn't work. So knowing how to get the most out of Puppet's debugging features can be a great help.

Printing out variable values

You can refer to variables in the message:

notify { "operatingsystem is ${::operatingsystem}": }

And Puppet...