reboot resource¶

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Use the reboot resource to reboot a node, a necessary step with some installations on certain platforms. This resource is supported for use on the Microsoft Windows, macOS, and Linux platforms.

Syntax¶

The reboot resource has the following syntax:

reboot 'name' do
  delay_mins      Integer # default value: 0
  reason          String # default value: Reboot by Chef
  action          Symbol # defaults to :nothing if not specified
end

where:

reboot 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.
delay_mins and reason are the properties available to this resource.

Actions¶

The reboot resource has the following actions:

:cancel: Cancel a reboot request.
: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.
:reboot_now: Reboot a node so that the chef-client may continue the installation process.
:request_reboot: Reboot a node at the end of a chef-client run.

Properties¶

The reboot resource has the following properties:

delay_mins

Ruby Type: Integer | Default Value: 0

The amount of time (in minutes) to delay a reboot request.

ignore_failure

Ruby Type: true, false | Default Value: false

Continue running a recipe if a resource fails for any reason.

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 timer is available:

:immediate, :immediately: Specifies that a notification should be run immediately, per resource notified.

reason

Ruby Type: String

A string that describes the reboot action.

retries

Ruby Type: Integer | Default Value: 0

The number of times to catch exceptions and retry the resource.

retry_delay

Ruby Type: Integer | Default Value: 2

The retry delay (in seconds).

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 timer is available:

:immediate, :immediately: Specifies that a notification should be run immediately, per resource notified.

Examples¶

The following examples demonstrate various approaches for using resources in recipes. If you want to see examples of how Chef uses resources in recipes, take a closer look at the cookbooks that Chef authors and maintains: https://github.com/chef-cookbooks.

Reboot a node immediately

reboot 'now' do
  action :nothing
  reason 'Cannot continue Chef run without a reboot.'
  delay_mins 2
end

execute 'foo' do
  command '...'
  notifies :reboot_now, 'reboot[now]', :immediately
end

Reboot a node at the end of a chef-client run

reboot 'app_requires_reboot' do
  action :request_reboot
  reason 'Need to reboot when the run completes successfully.'
  delay_mins 5
end

Cancel a reboot

reboot 'cancel_reboot_request' do
  action :cancel
  reason 'Cancel a previous end-of-run reboot request.'
end

Rename computer, join domain, reboot

The following example shows how to rename a computer, join a domain, and then reboot the computer:

reboot 'Restart Computer' do
  action :nothing
end

powershell_script 'Rename and Join Domain' do
  code <<-EOH
    ...your rename and domain join logic here...
  EOH
  not_if <<-EOH
    $ComputerSystem = gwmi win32_computersystem
    ($ComputerSystem.Name -like '#{node['some_attribute_that_has_the_new_name']}') -and
      $ComputerSystem.partofdomain)
  EOH
  notifies :reboot_now, 'reboot[Restart Computer]', :immediately
end

where:

The powershell_script resource block renames a computer, and then joins a domain
The reboot resource restarts the computer
The not_if guard prevents the Windows PowerShell script from running when the settings in the not_if guard match the desired state
The notifies statement tells the reboot resource block to run if the powershell_script block was executed during the chef-client run