Learning MCollective

Chapter 7. Configuration Management

By now you must be thinking to yourself, “Wow, this is a lot of configuration data.” Yes, you are absolutely right.

It is best to use Puppet, Chef, or another configuration-management system to deploy and maintain MCollective. As you proceed through this book, you will be constantly tweaking the MCollective configuration and adding new plugins. Most changes will need to be synchronized across servers, yet many servers will also have customized settings. In previous sections, we have gone over how to set up MCollective by hand, but across many systems it becomes a lot of work. It’s best to manage your MCollective installation with configuration management.

As the installation documentation on the Puppet Labs website says:

[MCollective] is the textbook example for why you need config management:

• It has multiple components that run on many different machines.

• It has pieces of global configuration that must be set harmoniously, everywhere.

• Most of its settings are identical for machines in a given role (e.g. every server), but some of its settings have per-system differences. This is easy to manage with a template, and incredibly frustrating to manage by hand.

• Its configuration will change over time, and the changes affect many many systems at once.

  New/updated agents must be deployed to all servers; when a new admin user is introduced, every server must be made aware of their permissions.

In summary, its configuration requirements are ...