Creating Environments

For more info about what environments do, see About Directory Environments.

Structure of an environment

An environment is just a directory that follows a few conventions:

• The directory name is the environment name.
• It must be located on the Puppet master server(s) in one of the environmentpath directories, usually $codedir/environments. (See the environmentpath section of the configuring environments page.)
• It should contain a modules directory. If present, it will become part of the environment’s default modulepath.
• It should contain a manifests directory, which will be the environment’s default main manifest.
• It may contain an environment.conf file, which can locally override several settings, including modulepath and manifest.

Allowed environment names

Environment names can contain lowercase letters, numbers, and underscores. That is, they must match the following regular expression:

\A[a-z0-9_]+\Z

What environments provide

An environment can define three resources the Puppet master will use when compiling catalogs for agent nodes:

• The modulepath
• The main manifest
• The config version script

The modulepath

The modulepath is the list of directories Puppet will load modules from. See the reference page on the modulepath for more details about how Puppet uses it.

The default modulepath

By default, the effective modulepath for a given environment will be:

<MODULES DIRECTORY FROM ENVIRONMENT>:$basemodulepath

That is, Puppet will add the environment’s modules directory to the value of the basemodulepath setting from puppet.conf, with the environment’s modules getting priority. If the modules directory is empty or absent, Puppet will only use modules from directories in the basemodulepath.

Configuring the modulepath

You can configure a different modulepath for an environment by setting modulepath in its environment.conf file. Note that the global modulepath setting from puppet.conf will never be used by an environment.

Note: In Puppet Enterprise, every environment must include /opt/puppetlabs/puppet/modules in its modulepath, since PE uses modules in that directory to configure its own infrastructure.

Environments already get this directory by default, since it’s part of the default value of basemodulepath. Don’t remove it from the basemodulepath setting, and if you override the modulepath in environment.conf, ensure your custom modulepath includes either $basemodulepath or /opt/puppetlabs/puppet/modules.

Checking the modulepath

You can view an environment’s effective modulepath by specifying the environment when requesting the setting value:

$ sudo puppet config print modulepath --section master --environment test
/etc/puppetlabs/code/environments/test/modules:/etc/puppetlabs/code/modules:/opt/puppetlabs/puppet/modules

The main manifest

The main manifest is Puppet’s starting point for compiling a catalog. See the reference page on the main manifest for more details.

The default main manifest

Unless you say otherwise in environment.conf, an environment will use Puppet’s global default_manifest setting to determine its main manifest.

The value of this setting can be an absolute path to a manifest that all environments will share, or a relative path to a file or directory inside each environment.

The default value of default_manifest is ./manifests — that is, the environment’s own manifests directory.

If the file or directory specified by default_manifest is empty or absent, Puppet will not fall back to any other manifest; instead, it will behave as though you used a totally blank main manifest. Note that the global manifest setting from puppet.conf will never be used by an environment.

Configuring the main manifest

You can configure a different main manifest for an environment by setting manifest in its environment.conf file.

As with the global default_manifest setting, you can specify a relative path (to be resolved within the environment’s directory) or an absolute path.

Locking the main manifest

If you want to prevent any environment from setting its own main manifest, you can lock all environments to a single global manifest with the disable_per_environment_manifest setting. For details, see the docs for this setting.

The config version script

Puppet automatically adds a config version to every catalog it compiles, as well as to messages in reports. The version is an arbitrary piece of data that can be used to identify catalogs and events.

The default config version

By default, the config version will be the time at which the catalog was compiled (as the number of seconds since January 1, 1970).

Configuring the config version

You can specify an executable script that will determine an environment’s config version by setting config_version in its environment.conf file. Puppet will run this script when compiling a catalog for a node in the environment, and use its output as the config version. Note that the global config_version setting from puppet.conf will never be used by an environment.

Note: If you’re using a system binary like git rev-parse, make sure to specify the absolute path to it! If config_version is set to a relative path, Puppet will look for the binary in the environment, not in the system’s PATH.

The environment.conf File

An environment can contain an environment.conf file, which can override values for certain settings.

In this version of Puppet, the environment.conf file is only allowed to override five settings:

• modulepath
• manifest
• config_version
• environment_timeout
• static_catalogs

See the page on environment.conf for more details.