Chapter 2. Knife and Its Associated Plugins

We learned about the Chef ecosystem in the last chapter and, as we saw, Knife is one of those tools that we'll be using the most while doing development. In this chapter, we'll look at the internals of Knife and we'll also see different plugins, which will make your life a lot easier while managing your infrastructure using Chef.

Introducing Knife

Knife is a command-line tool that comes bundled with the Chef installation. Depending upon how Chef was installed, you may find the binary at any particular location on your workstation. Since I have installed Chef using rvm and gem packaging, it is found at ~/.rvm/gems/ruby-2.1.0/gems/chef-11.8.2/bin/knife.

Depending upon your setup, you may find it at some other location. Whatever the location, ensure that it is in your PATH variable.

Knife is used for almost every aspect of managing your interactions with chef-server. It helps us manage:

• Cookbooks

• Environments

• Roles

• Data bags

• Nodes

• API clients

• Bootstrapping of instances

• Searching for nodes

Let's see what the knife command has to offer to us. Just fire up the terminal and enter the command:

$knife
ERROR: You need to pass a sub-command (e.g., knife SUB-COMMAND)
Usage: knife sub-command (options)
    -s, --server-url URL             Chef Server URL
        --chef-zero-port PORT        Port to start chef-zero on
    -k, --key KEY ...

Summary

In this chapter, we learned about one of the most widely used components of Chef's ecosystem, called Knife. We looked at the different subcommands of Knife, configuring Knife, and finally some plugins that can be used to extend Knife's functionality.

In the next chapter, we will see why we need to learn Ruby and write efficient infrastructure code using Ruby.