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
$codedir/environments. (See the
environmentpathsection of the configuring environments page.)
- It should contain a
modulesdirectory. If present, it will become part of the environment’s default
- It should contain a
manifestsdirectory, which will be the environment’s default main manifest.
- It may contain an
environment.conffile, which can locally override several settings, including
Allowed environment names
Environment names can contain lowercase letters, numbers, and underscores. That is, they must match the following regular expression:
What environments provide
An environment can define three resources the Puppet master will use when compiling catalogs for agent nodes:
- The modulepath
- The main manifest
- The config version script
The modulepath is the list of directories Puppet will load modules from. See the reference page on the modulepath for more details about how Puppet uses it.
The default modulepath
By default, the effective modulepath for a given environment will be:
<MODULES DIRECTORY FROM ENVIRONMENT>:$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
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/modulesin 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
basemodulepathsetting, and if you override the modulepath in environment.conf, ensure your custom modulepath includes either
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
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
./manifests — that is, the environment’s own
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
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: