kernel_module resource¶

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Use the kernel_module resource to manage kernel modules on Linux systems. This resource can load, unload, blacklist, install, and uninstall modules.

New in Chef Client 14.3.

Syntax¶

The kernel_module resource has the following syntax:

kernel_module 'name' do
  load_dir        String # default value: /etc/modules-load.d
  modname         String # default value: 'name' unless specified
  unload_dir      String # default value: /etc/modprobe.d
  action          Symbol # defaults to :install if not specified
end

where:

kernel_module is the resource.
name is the name given to the resource block.
action identifies which steps the chef-client will take to bring the node into the desired state.
load_dir, modname, and unload_dir are the properties available to this resource.

Actions¶

The kernel_module resource has the following actions:

:blacklist: Blacklist a kernel module.
:install: Default. Load kernel module, and ensure it loads on reboot.
:load: Load a kernel module.
:uninstall: Unload a kernel module and remove module config, so it doesn’t load on reboot.
:unload: Unload kernel module.
:nothing: Define this resource block to do nothing until notified by another resource to take action. When this resource is notified, this resource block is either run immediately or it is queued up to be run at the end of the Chef Client run.

Properties¶

The kernel_module resource has the following properties:

load_dir

Ruby Type: String | Default Value: /etc/modules-load.d

The directory to load modules from.

modname

Ruby Type: String | Default Value: 'name'

The name of the kernel module.

notifies

Ruby Type: Symbol, ‘Chef::Resource[String]’

A resource may notify another resource to take action when its state changes. Specify a 'resource[name]', the :action that resource should take, and then the :timer for that action. A resource may notify more than one resource; use a notifies statement for each resource to be notified.

A timer specifies the point during the Chef Client run at which a notification is run. The following timers are available:

:before: Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed: Default. Specifies that a notification should be queued up, and then executed at the end of the Chef Client run.
:immediate, :immediately: Specifies that a notification should be run immediately, per resource notified.

The syntax for notifies is:

notifies :action, 'resource[name]', :timer

subscribes

Ruby Type: Symbol, ‘Chef::Resource[String]’

A resource may listen to another resource, and then take action if the state of the resource being listened to changes. Specify a 'resource[name]', the :action to be taken, and then the :timer for that action.

Note that subscribes does not apply the specified action to the resource that it listens to - for example:

file '/etc/nginx/ssl/example.crt' do
   mode '0600'
   owner 'root'
end

service 'nginx' do
   subscribes :reload, 'file[/etc/nginx/ssl/example.crt]', :immediately
end

In this case the subscribes property reloads the nginx service whenever its certificate file, located under /etc/nginx/ssl/example.crt, is updated. subscribes does not make any changes to the certificate file itself, it merely listens for a change to the file, and executes the :reload action for its resource (in this example nginx) when a change is detected.

A timer specifies the point during the Chef Client run at which a notification is run. The following timers are available:

:before: Specifies that the action on a notified resource should be run before processing the resource block in which the notification is located.
:delayed: Default. Specifies that a notification should be queued up, and then executed at the end of the Chef Client run.
:immediate, :immediately: Specifies that a notification should be run immediately, per resource notified.

The syntax for subscribes is:

subscribes :action, 'resource[name]', :timer

unload_dir

Ruby Type: String | Default Value: /etc/modprobe.d

The modprobe.d directory.