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9.2. Parameters

Red Hat Satellite parameters define key-value pairs to use when provisioning hosts. These are similar to Puppet's concept of a default scope parameter. You can define parameters when setting up a host with Puppet.

Types of Parameters

Red Hat Satellite has two types of parameters:
Simple Parameters
String parameters that define a relationship between a key and value pair. They cannot be overridden by user configuration, but they are overridden according to Satellite's parameter hierarchy. The following parameters are simple parameters in Red Hat Satellite: Global, organization-level, location-level, domain-level, operating system level, host group, and host parameters.
Smart Parameters
Complex parameters that define a value for a key but allow conditional arguments, validation, and overrides for specific object types. Smart parameters enable a Puppet class to get external data. They are used in Puppet Classes called parameterized classes in Puppet terminology. The hierarchy for these parameters can be configured the in the web UI.
The following parameter hierarchy applies for simple parameters:
Global Parameters
Default parameters that apply to every host in Satellite. Configured in Configure → Global parameters.
Organization-level parameters
Parameters that affect all hosts in a given organization. Organization-level parameters override Global parameters. Configured in Administer → Organizations → Edit → Parameters.
Location-level parameters
Parameters that affect all hosts in a given location. Location-level parameters override Organization-level and Global parameters. Configured in Administer → Locations → Edit → Parameters
Domain Parameters
Parameters that affect all hosts in a given domain. Domain parameters override Location-level and higher parameters. Configured in Infrastructure → Domains → [choose_a_domain] → Parameters.
Operating System Level Parameters
Parameters that affect all hosts with a given operating system. Operating system level parameters override Domain and higher parameters. Configured in Hosts → Operating systems → [choose_an_operating_system] → Parameters.
Host Group Parameters
Parameters that affect all hosts in a given Host Group. Host Group parameters override Operating system level and higher parameters. Configured in Configure → Host Groups → [choose_a_host_group] → Parameters.
Host Parameters
Parameters that affect a specific host. All previously inherited parameters are visible on the Parameters subtab and can be overridden. Configured in Hosts → All hosts → Edit → Parameters.

Using Parameters with Puppet Classes

Red Hat Satellite has two ways to supply values to a Puppet Master for a host to use with a Puppet class:
Smart Variables
A tool to provide global parameters to the Puppet Master, in key-value form, for classes that do not have Smart parameters. They enable overriding parameter values in a Puppet manifest. They are intended for use when a class does not have Smart parameters or in special cases when a global parameter is desired. They can have multiple possible values, all depending on hierarchical context or various conditions a user can apply. They existed before Puppet had parameterized classes and today are kept either for backward compatibility or for the use of global parameters where you want validations, to use only with specific Puppet classes, and for types other than string (because otherwise you could just use the simple parameters).
Parameterized Classes
Puppet classes containing Smart parameters. The classes are imported from the Puppet Master and the name of the parameter, for example $::name (preferred) or $name, is defined by the person who wrote the class and cannot be changed. They enable you to decide the value of the variable for a specific class rather than globally.
Configured parameters are included in each host's corresponding YAML file and sent to the Puppet Master. The YAML file can be viewed in the web UI on the page for a specific host. You should not manually change the /etc/foreman/settings.yaml configuration file because they are overwritten the next time you run the satellite-installer command.

Important

Parameterized class support is enabled by default in Satellite 6. If required to ensure that it is, navigate to Administer → Settings, select the Puppet tab, and ensure the Parametrized_Classes_in_ENC is set to True.

9.2.1. Creating a Global Simple Parameter

This procedure shows how to add a new global parameter to Satellite.

Procedure 9.2. To Create a Global Simple Parameter:

  1. Click Configure → Global Parameters.
  2. Click New Parameter.
  3. Type a Name for the parameter's key.
  4. Enter a Value for the parameter.
  5. Optionally select if you want the value to be hidden in the web UI.
  6. Click Submit.

9.2.2. Configuring Smart Variables

The following procedure configures Smart Variables to override a value in a Puppet class.

Procedure 9.3. To Configure Smart Variables:

  1. Click Configure → Puppet Classes.
  2. Select a class from the list.
  3. Click the Smart Variables tab. This displays a new screen. The left section contains a list of possible parameters the class supports. The right section contains the configuration options for the parameter selected. Click the Add Variable to add a new parameter. Otherwise, select a parameter from the left-hand list.
  4. Type a name for the parameter in the Key field.
  5. Edit the Description text box to add any plain text notes.
  6. Select the Key type of data to pass. This is most commonly a string, but other data types are supported.
  7. Enter a Default Value for the parameter to be sent to the Puppet Master if no host match occurs.
  8. Optionally select Hidden value if the field contains data you do not want to be displayed while you are working.
  9. Use the Optional Input Validator section to restrict the allowed values for the parameter. Choose a Validator type (either a list of comma separated values or a regular expression, regexp) and input the allowed values or regular expression code in the Validator rule field.
  10. The Prioritize attribute order section provides options for overriding values for specific hosts based upon conditional arguments. The attribute type and its value is known as a matcher.
    1. Set the Order of precedence in which the host attributes or Facts are to be evaluated against the matchers by arranging the entries in the list. You can add to the default list. To create a logical AND condition between matchers, arrange them on one line as a comma separated list.
    2. Click Add Matcher to add a conditional argument. The attributes to match against should correspond to the entries in the Order list. If no matcher is configured then only the default value can be used for the override feature.
      For example, if the desired value of the parameter to be supplied to the Puppet Master is test for any host with a fully qualified domain name of server1.example.com, then specify the matcher as fqdn=server1.example.com and the Value as test.
      The precedence for matching is as follows:
      1. If the matcher is a host attribute, use that.
      2. If there are no attributes with that name, look for a matching host parameter (which is inherited according to the parameter hierarchy).
      3. If there is still no match, check the host Facts.
      It is recommend to use an attribute that is present in Facter and cannot be confused with a host attribute. Host attributes can be either host parameters or associations to the host, such as host group, domain, and organization. The matcher must only be something the host has one of, for example config group cannot be used because the host can have many config groups but a host only has one location so location is a valid matcher.
      Dynamic data is possible by using parameters and Puppet Facts in the Value field in Embedded Ruby (ERB) template syntax. For example, to use a Puppet Fact as part of the value: 
      <%= @host.facts['network_eth0'] %>
      To list available Puppet Facts navigate to Monitor → Facts.
  11. Click Submit to save your changes.
For further information on working with Puppet modules see Adding Puppet Modules to Red Hat Satellite 6. For more information on ERB syntax see Appendix A, Template Writing Reference.

9.2.3. Importing Parameterized Classes from a Puppet Master

The following procedure imports parameterized classes from your Puppet Master.

Note

The import of parameterized classes happens automatically if your Puppet modules are managed via a Product and a Content View.

Procedure 9.4. To Import Parameterized Classes:

  1. In the Satellite web UI, select from the context menu Any Organization and Any Location.
  2. Click Configure → Puppet Classes.
  3. Click Import from Host Name to import parameterized classes from your Puppet Master.
  4. The Puppet Classes page displays with the new classes listed.

9.2.4. Configuring Smart Class Parameters

The following procedure configures parameters within a class. Classes that contain parameters are referred to as parameterized classes.

Procedure 9.5. To Configure Smart Class Parameters:

  1. Click Configure → Puppet Classes.
  2. Select a class from the list that has parameters as indicated in the Parameters column.
  3. Click the Smart Class Parameter tab. This displays a new screen. The left section contains a list of possible parameters the class supports. The right section contains the configuration options for the parameter selected.
  4. Select a parameter from the left-hand list.
  5. Edit the Description text box to add any plain text notes.
  6. Select Override to allow Satellite control over this variable. If the check box is not selected, Satellite does not pass the new variable to Puppet.
  7. Select the Key type of data to pass. This is most commonly a string, but other data types are supported.
  8. Enter a Default Value for the parameter to be sent to the Puppet Master if no host match occurs.
  9. Optionally select Use Puppet Default to not send a value to the Puppet Master unless an override match occurs.
  10. Optionally select Hidden value if the field contains data you do not want to be displayed while you are working.
  11. Use the Optional input validator section to restrict the allowed values for the parameter. Choose a Validator type (either a list of comma separated values or a regular expression, regexp) and input the allowed values or regular expression code in the Validator rule field.
  12. The Prioritize attribute order section will appear if the Override option is selected. This provides options for overriding values for specific hosts based upon conditional arguments. The attribute type and its value is known as a matcher.
    1. Set the Order of precedence in which the host attributes or Facts are to be evaluated against the matchers by arranging the entries in the list. You can add to the default list. To create a logical AND condition between matchers, arrange them on one line as a comma separated list.
    2. Click Add Matcher to add a conditional argument. The attributes to match against should correspond to the entries in the Order list. If no matcher is configured then only the default value can be used for the override feature.
      For example, if the desired value of the parameter to be supplied to the Puppet Master is test for any host with a fully qualified domain name of server1.example.com, then specify the matcher as fqdn=server1.example.com and the Value as test.
      The precedence for matching is as follows:
      1. If the matcher is a host attribute, use that.
      2. If there are no attributes with that name, look for a matching host parameter (which is inherited according to the parameter hierarchy).
      3. If there is still no match, check the host Facts.
      It is recommend to use an attribute that is present in Facter and cannot be confused with a host attribute.
      Dynamic data is possible by using parameters and Puppet Facts in the Value field in Embedded Ruby (ERB) template syntax. For example, to use a Puppet Fact as part of the value: 
      <%= @host.facts['network_eth0'] %>
      To list available Puppet Facts navigate to Monitor → Facts.
  13. Click Submit to save your changes.
For further information on working with Puppet modules see Adding Puppet Modules to Red Hat Satellite 6. For more information on ERB syntax see Appendix A, Template Writing Reference.