chef-client Cookbook

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

Requirements

• Chef 0.10.14+
• Ohai 0.6.12+

Chef 10.14.0 or greater is recommended to make use of the
client_fork
configuration option.

Platforms

The following platforms are tested directly under test-kitchen; see .kitchen.yml and TESTING.md for details.

• Ubuntu 10.04, 12.04
• CentOS 5.9, 6.4
• Debian 6.0.7
• SUSE (SLES) 11-sp2
• OmniOS r151006c

The following platforms are known to work:

• Debian family (Debian, Ubuntu etc)
• Red Hat family (Redhat, CentOS, Oracle etc)
• Fedora family
• SUSE distributions (OpenSUSE, SLES, etc)
• ArchLinux
• FreeBSD
• Mac OS X
• Mac OS X Server

Other platforms may work with or without modification. Most notably, attribute modification may be required.

Opscode Cookbooks

Some cookbooks can be used with this cookbook but they are not explicitly required. The default settings in this cookbook do not require their use. The other cookbooks (on community.opscode.com) are:

• bluepill
• daemontools
• runit

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

See USAGE below.

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 in Chef::Config[:log_location] via command-line option to a location where chef-client should log output. Default "/var/log/chef".
• 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 hour that chef-client will run as a cron task, only applicable if the you set "cron" as the "init_style"
• node["chef_client"]["cron"]["hour"] - The hour that chef-client will run as a cron task, only applicable if the you set "cron" as the "init_style"
• 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 chef-client output.
• node["chef_client"]["cron"]["use_cron_d"] - If true, use the "cron_d" LWRP (https://github.com/opscode-cookbooks/cron). 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"]["daemon_options"] - An array of additional options to pass to the chef-client service, empty by default, and must be an array if specified.

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 below.
• 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.

Deprecated / Replaced

The following attributes are deprecated at the ['chef_client'] attribute level. Set them using the indicated ['chef_client']['config'] attribute.

• node['chef_client']['environment'] - Set the node's environment directly (e.g., knife bootstrap -E), as it makes it easier to move nodes to different environments.
• node['chef_client']['log_level'] - Not set anymore, use the default log level and output formatting from 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 from Chef 11. This can still be set using node['chef_client']['config']['verbose_logging'] if required.

The following attributes are deprecated entirely.

• node['chef_client']['checksum_cache_skip_expires'] - No longer required in Chef 11.

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 below 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]

To set up the chef-client under bluepill, daemontools or runit, those recipes 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 them. For example, to use runit:

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.
• arch - uses the init script included in this cookbook for ArchLinux, supported on arch.
• runit - sets up the service under runit, supported on ubuntu, debian, EL-family distributions, and gentoo.
• bluepill - sets up the service under bluepill. As bluepill is a pure ruby process monitor, this should work on any platform.
• daemontools - sets up the service under daemontools, supported on debian, ubuntu and arch
• launchd - sets up the service under launchd, supported on Mac OS X & Mac OS X Server. (this requires Chef >= 0.10.10)
• bsd - prints a message about how to update BSD systems to enable the chef-client service, supported on Free/OpenBSD.

default

Includes the chef-client::service recipe by default.

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.

Note If you're using this on a Chef 10 Server, be aware of using this recipe. First copy the validation.pem certificate file to another location, such as your knife configuration directory (~/.chef) or Chef Repository.

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.

Usage

Use the recipes as described above to configure your systems to run Chef as a service via cron 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.opscode.com/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 aware of 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.vmware.com:3128",
      "https_proxy" => "http://proxy.vmware.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 '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 'rubygems'
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)

(Hat tip to Joseph Holsten for this in COOK-2326

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 this 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 Opscode's 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 above:

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

Runit

To use runit, download the cookbook from the cookbook site.

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.

Bluepill

To use bluepill, download the cookbook from the cookbook site.

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

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

The chef-client recipe will create the chef-client service configured with bluepill. The bluepill "pill" will be located in /etc/bluepill/chef-client.pill. The output log will be to client.log file in the node["chef_client"]["log_dir"] location, /var/log/chef/client by default.

Daemontools

To use daemontools, download the cookbook from the cookbook site.

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

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

The chef-client recipe will create the chef-client service configured under daemontools. It uses the same sv run scripts as the runit recipe. The run script will be located in /etc/sv/chef-client/run. The output log will be in the daemontools 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". Launchd support for the service resource is only supported from Chef 0.10.10 onwards. An error message will be logged if you try to use the launchd service for chef-client on a Chef version that does not contain this launchd support.

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".

License & Authors

• Author:: Joshua Timberman (joshua@opscode.com)
• Author:: Paul Mooring (paul@opscode.com)
• Author:: Seth Chisamore (schisamo@opscode.com)

Copyright:: 2010-2013, Opscode, 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.