Chef Client Cookbook

This cookbook is used to configure a system as a Chef Client.

Requirements

Platforms

• AIX 6+
• Debian 7+
• Fedora
• FreeBSD 9+
• Mac OS X
• openSUSE 13+
• SLES 12+
• RHEL 5+
• Solaris 10+
• Ubuntu 12.04+
• Windows 2008 R2+

Chef

• Chef 12.1+

Dependent Cookbooks

The runit cookbook can be used with this cookbook but it is not explicitly required. The default settings in this cookbook do not require its use.

Cron is a dependency, for default behavior of the cron recipe to work. This is a dependency because cron is cross platform, and doesn't carry additional dependencies, unlike the other cookbooks listed above.

• cron 1.7.0+
• logrotate 1.9.0+
• windows 1.42.0+

See USAGE.

Attributes

The following attributes affect the behavior of the chef-client program when running as a service through one of the service recipes, or in cron with the cron recipe, or are used in the recipes for various settings that require flexibility.

• node['chef_client']['interval'] - Sets Chef::Config[:interval] via command-line option for number of seconds between chef-client daemon runs. Default 1800.
• node['chef_client']['splay'] - Sets Chef::Config[:splay] via command-line option for a random amount of seconds to add to interval. Default 300.
• node['chef_client']['log_dir'] - Sets directory used to store chef-client logs. Default "/var/log/chef".
• node['chef_client']['log_rotation']['options'] - Set options to logrotation of chef-client log file. Default ['compress'].
• node['chef_client']['log_rotation']['prerotate'] - Set prerotate action for chef-client logrotation. Default to nil.
• node['chef_client']['log_rotation']['postrotate'] - Set postrotate action for chef-client logrotation. Default to chef-client service reload depending on init system.
• node['chef_client']['conf_dir'] - Sets directory used via command-line option to a location where chef-client search for the client config file . Default "/etc/chef".
• node['chef_client']['bin'] - Sets the full path to the chef-client binary. Mainly used to set a specific path if multiple versions of chef-client exist on a system or the bin has been installed in a non-sane path. Default "/usr/bin/chef-client".
• node['chef_client']['cron']['minute'] - The minute that chef-client will run as a cron task. See cron recipe
• node['chef_client']['cron']['hour'] - The hour that chef-client will run as a cron task. See cron recipe
• node['chef_client']['cron']['weekday'] - The weekday that chef-client will run as a cron task. See cron recipe
• node['chef_client']['cron']['environment_variables'] - Environment variables to pass to chef-client's execution (e.g. SSL_CERT_FILE=/etc/ssl/certs/ca-certificates.crt chef-client)
• node['chef_client']['cron']['log_file'] - Location to capture the log output of chef-client during the chef run.
• node['chef_client']['cron']['append_log'] - Whether to append to the log. Default: false chef-client output.
• node['chef_client']['cron']['use_cron_d'] - If true, use the cron_d resource. If false (default), use the cron resource built-in to Chef.
• node['chef_client']['cron']['mailto'] - If set, MAILTO env variable is set for cron definition
• node['chef_client']['reload_config'] - If true, reload Chef config of current Chef run when client.rb template changes (defaults to true)
• node['chef_client']['daemon_options'] - An array of additional options to pass to the chef-client service, empty by default, and must be an array if specified.
• node['chef_client']['task']['frequency'] - Frequency with which to run the chef-client scheduled task (e.g., 'hourly', 'daily', etc.) Default is 'minute'.
• node['chef_client']['task']['frequency_modifier'] - Numeric value to go with the scheduled task frequency. Default is node['chef_client']['interval'].to_i / 60
• node['chef_client']['task']['start_time'] - The start time for the task in HH:mm format. If the frequency is minute default start time will be Time.now plus the frequency_modifier number of minutes.
• node['chef_client']['task']['user'] - The user the scheduled task will run as, defaults to 'SYSTEM'.
• node['chef_client']['task']['password'] - The password for the user the scheduled task will run as, defaults to nil because the default user, 'SYSTEM', does not need a password.

The following attributes are set on a per-platform basis, see the attributes/default.rb file for default values.

• node['chef_client']['init_style'] - Sets up the client service based on the style of init system to use. Default is based on platform and falls back to 'none'. See service recipes.

• node['chef_client']['run_path'] - Directory location where chef-client should write the PID file. Default based on platform, falls back to "/var/run".

• node['chef_client']['cache_path'] - Directory location for

• Chef::Config[:file_cache_path] where chef-client will cache various files. Default is based on platform, falls back to "/var/chef/cache".

• node['chef_client']['backup_path'] - Directory location for Chef::Config[:file_backup_path] where chef-client will backup templates and cookbook files. Default is based on platform, falls back to "/var/chef/backup".

• node['chef_client']['launchd_mode'] - (Only for Mac OS X) if set to 'daemon', runs chef-client with -d and -s options; defaults to 'interval'.

• When chef_client['log_file'] is set and running on a logrotate supported platform (debian, rhel, fedora family), use the following attributes to tune log rotation.

  • node['chef_client']['logrotate']['rotate'] - Number of rotated logs to keep on disk, default 12.
  • node['chef_client']['logrotate']['frequency'] - How often to rotate chef client logs, default weekly.

This cookbook makes use of attribute-driven configuration with this attribute. See USAGE for examples.

• node['chef_client']['config'] - A hash of Chef::Config keys and their values, rendered dynamically in /etc/chef/client.rb.
• node['chef_client']['load_gems'] - Hash of gems to load into chef via the client.rb file
• node['ohai']['disabled_plugins'] - An array of ohai plugins to disable, empty by default, and must be an array if specified. Ohai 6 plugins should be specified as a string (ie. "dmi"). Ohai 7+ plugins should be specified as a symbol within quotation marks (ie. ":Passwd").
• node['ohai']['plugin_path'] - An additional path to load Ohai plugins from. Necessary if you use the ohai_plugin resource in the Ohai cookbook to install your own ohai plugins.

Chef Client Config

The following attributes should be set using ['chef_client']['config']. Setting them at the ['chef_client'] attribute level is deprecated.

• node['chef_client']['environment'] - Set the node's environment directly (useful for unattended installs when knife bootstrap -E is not an option).
• node['chef_client']['log_level'] - Not set anymore, use the default log level and output formatting in Chef 11+.
• node['chef_client']['server_url'] - Set by default with
• node['chef_client']['config']['chef_server_url']
• node['chef_client']['validation_client_name'] - Set by default with node['chef_client']['config']['validation_client_name'].
• node['chef_client']['report_handlers'] - See USAGE for how to set handlers with the config attribute.
• node['chef_client']['exception_handlers'] - See USAGE for how to set handlers with the config attribute.
• node['chef_client']['checksum_cache_path'] - Use
• node['chef_client']['config']['cache_options']['path'].
• node['chef_client']['verbose_logging'] - Not set anymore, we recommend using the default log level and output formatting in Chef 11+. This can still be set using node['chef_client']['config']['verbose_logging'] if required.

Recipes

This section describes the recipes in the cookbook and how to use them in your environment.

config

Sets up the /etc/chef/client.rb config file from a template and reloads the configuration for the current chef-client run.

See USAGE for more information on how the configuration is rendered with attributes.

service recipes

The chef-client::service recipe includes one of the chef-client::INIT_STYLE_service recipes based on the attribute, node['chef_client']['init_style']. The individual service recipes can be included directly, too. For example, to use the init scripts, on a node or role's run list:

recipe[chef-client::init_service]

To set up the chef-client under runit, the runit cookbook must be specified on the node or role's run list first, to ensure that the dependencies are resolved, as this cookbook does not directly depend on runit. For example:

recipe[runit]
recipe[chef-client::runit_service]

Use this recipe on systems that should have a chef-client daemon running, such as when Knife bootstrap was used to install Chef on a new system.

• init - uses the init script included in this cookbook, supported on debian and redhat family distributions.
• upstart - uses the upstart job included in this cookbook, supported on ubuntu.
• runit - sets up the service under runit, supported on ubuntu, debian, redhat family distributions, and gentoo.
• launchd - sets up the service under launchd, supported on Mac OS X & Mac OS X Server.
• bsd - prints a message about how to update BSD systems to enable the chef-client service.
• systemd - sets up the service under systemd. Supported on systemd based distros.

default

Includes the chef-client::service recipe by default on *nix platforms and the task recipe for Windows hosts.

delete_validation

Use this recipe to delete the validation certificate (default /etc/chef/validation.pem) when using a chef-client after the client has been validated and authorized to connect to the server.

cron

Use this recipe to run chef-client as a cron job rather than as a service. The cron job runs after random delay that is between 0 and 90 seconds to ensure that the chef-clients don't attempt to connect to the chef-server at the exact same time. You should set node['chef_client']['init_style'] = 'none' when you use this mode but it is not required.

task

Use this recipe to run chef-client on Windows nodes as a scheduled task. Without modifying attributes the scheduled task will run 30 minutes after the recipe runs, with each chef run rescheduling the run 30 minutes in the future. By default the job runs as the system user. The time period between runs can be modified with the default['chef_client']['task']['frequency_modifier'] attribute and the user can be changed with the default['chef_client']['task']['user'] and default['chef_client']['task']['password'] attributes.

Usage

Use the recipes as described above to configure your systems to run Chef as a service via cron / scheduled task or one of the service management systems supported by the recipes.

The chef-client::config recipe is only required with init style init (default setting for the attribute on debian/redhat family platforms, because the init script doesn't include the pid_file option which is set in the config.

The config recipe is used to dynamically generate the /etc/chef/client.rb config file. The template walks all attributes in node['chef_client']['config'] and writes them out as key:value pairs. The key should be the configuration directive. For example, the following attributes (in a role):

default_attributes(
  "chef_client" => {
    "config" => {
      "ssl_verify_mode" => ":verify_peer",
      "client_fork" => true
    }
  }
)

will render the following configuration (/etc/chef/client.rb):

chef_server_url "https://api.chef.io/organizations/MYORG"
validation_client_name "MYORG-validator"
ssl_verify_mode :verify_peer
node_name "config-ubuntu-1204"
client_fork true

The chef_server_url, node_name and validation_client_name are set by default in the attributes file from Chef::Config. They are presumed to come from the knife bootstrap command when setting up a new node for Chef. To set the node name to the default value (the node['fqdn'] attribute), it can be set false. Be careful when setting this or the Server URL, as those values may already exist.

As another example, to set HTTP proxy configuration settings. By default Chef will not use a proxy.

default_attributes(
  "chef_client" => {
    "config" => {
      "http_proxy" => "http://proxy.mycorp.com:3128",
      "https_proxy" => "http://proxy.mycorp.com:3128",
      "http_proxy_user" => "my_username",
      "http_proxy_pass" => "Awe_some_Pass_Word!",
      "no_proxy" => "*.vmware.com,10.*"
    }
  }
)

Configuration Includes

The /etc/chef/client.rb file will include all the configuration files in /etc/chef/client.d/*.rb. To create custom configuration, simply render a file resource with file (and the content parameter), template, remote_file, or cookbook_file. For example, in your own cookbook that requires custom Chef client configuration, create the following cookbook_file resource:

chef_gem 'syslog-logger'

cookbook_file "/etc/chef/client.d/myconfig.rb" do
  source "myconfig.rb"
  mode 00644
  notifies :create, "ruby_block[reload_client_config]"
end

include_recipe 'chef-client::config'

Then create files/default/myconfig.rb with the configuration content you want. For example, if you wish to create a configuration to log to syslog:

require 'syslog-logger'
require 'syslog'

Logger::Syslog.class_eval do
  attr_accessor :sync, :formatter
end

log_location Logger::Syslog.new('chef-client', ::Syslog::LOG_DAEMON)

Or, if you're using Chef >= 12.4:

log_location Chef::Log::Syslog.new('chef-client', ::Syslog::LOG_DAEMON)

Requiring Gems

Use the load_gems attribute to install gems that need to be required in the client.rb. This attribute should be a hash. The gem will also be installed with chef_gem. For example, suppose we want to use a Chef Handler Gem, chef-handler-updated-resources, which is used in the next heading. Set the attributes, e.g., in a role:

default_attributes(
  "chef_client" => {
    "load_gems" => {
      "chef-handler-updated-resources" => {
        "require_name" => "chef/handler/updated_resources",
        "version" => "0.1"
      }
    }
  }
)

Each key in load_gems is the name of a gem. Each gem hash can have two keys, the require_name which is the string that will be require'd in /etc/chef/client.rb, and version which is the version of the gem to install. If the version is not specified, the latest version will be installed.

The above example will render the following in /etc/chef/client.rb:

["chef/handler/updated_resources"].each do |lib|
  begin
    require lib
  rescue LoadError
    Chef::Log.warn "Failed to load #{lib}. This should be resolved after a chef run."
  end
end

Start, Report, Exception Handlers

To dynamically render configuration for Start, Report, or Exception handlers, set the following attributes in the config attributes:

• start_handlers
• report_handlers
• exception_handlers

This is an alternative to using the chef_handler cookbook.

Each of these attributes must be an array of hashes. The hash has two keys, class (a string), and arguments (an array). For example, to use the report handler in the Requiring Gems section:

default_attributes(
  "chef_client" => {
    "config" => {
      "report_handlers" => [
        {"class" => "SimpleReport::UpdatedResources", "arguments" => []}
      ]
    }
  }
)

If the handler you're using has an initialize method that takes arguments, then pass each one as a member of the array. Otherwise, leave it blank as above.

This will render the following in /etc/chef/client.rb.

report_handlers << SimpleReport::UpdatedResources.new()

Alternate Init Styles

The alternate init styles available are:

• runit
• none -- should be specified if you are running chef-client as cron job

Runit

To use runit, download the cookbook from Supermarket.

Change the init_style to runit in the base role and add the runit recipe to the role's run list:

name "base"
description "Base role applied to all nodes"
default_attributes(
  "chef_client" => {
    "init_style" => "runit"
  }
)
run_list(
  "recipe[chef-client::delete_validation]",
  "recipe[runit]",
  "recipe[chef-client]"
)

The chef-client recipe will create the chef-client service configured with runit. The runit run script will be located in /etc/sv/chef-client/run. The output log will be in the runit service directory, /etc/sv/chef-client/log/main/current.

Launchd

On Mac OS X and Mac OS X Server, the default service implementation is "launchd".

Since launchd can run a service in interval mode, by default chef-client is not started in daemon mode like on Debian or Ubuntu. Keep this in mind when you look at your process list and check for a running chef process! If you wish to run chef-client in daemon mode, set attribute chef_client.launchd_mode to "daemon".

Installing and updating chef-client

This cookbook does not handle updating the chef-client, as that's out of the cookbook's current scope. To sensibly manage updates of the chef-client omnibus install, we refer you to:

• omnibus_updater - Heavy Water's cookbook for installing the omnibus Chef package and keeping your install up-to-date

For more on why this cookbook does not support installs, see Issue #102

License & Authors

Author: Cookbook Engineering Team (cookbooks@chef.io)

Copyright: 2010-2016, Chef Software, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.