chef-solo

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chef-solo is a command that executes chef-client in a way that does not require the Chef server in order to converge cookbooks. chef-solo uses chef-client’s Chef local mode, and does not support the following functionality present in chef-client / server configurations:

  • Centralized distribution of cookbooks
  • A centralized API that interacts with and integrates infrastructure components
  • Authentication or authorization

Note

chef-solo can be run as a daemon.

Cookbooks

chef-solo supports two locations from which cookbooks can be run:

  • A local directory.
  • A URL at which a tar.gz archive is located.

Using a tar.gz archive is the more common approach, but requires that cookbooks be added to an archive. For example:

$ tar zcvf chef-solo.tar.gz ./cookbooks

If multiple cookbook directories are being used, chef-solo expects the tar.gz archive to have a directory structure similar to the following:

cookbooks/
  |---- cbname1/
    |--attributes/ ... etc
  ...
  |---- cbname2/
    |--attributes/

The cookbook_path variable in the solo.rb file must include both directories. For example:

$ tar zcvf chef-solo.tar.gz ./cookbooks ./site-cookbooks

When the tar.gz archive contains all of the cookbooks required by chef-solo, upload it to the web server from which chef-solo will access the archive.

Nodes

Unlike chef-client, where the node object is stored on the Chef server, chef-solo stores its node objects as JSON files on local disk. By default, chef-solo stores these files in a nodes folder in the same directory as your cookbooks directory. You can control the location of this directory via the node_path value in your configuration file.

Attributes

chef-solo does not interact with the Chef server. Consequently, node-specific attributes must be located in a JSON file on the target system, a remote location (such as Amazon Simple Storage Service (S3)), or a web server on the local network.

The JSON file must also specify the recipes that are part of the run-list. For example:

{
  "resolver": {
    "nameservers": [ "10.0.0.1" ],
    "search":"int.example.com"
  },
  "run_list": [ "recipe[resolver]" ]
}

Data Bags

A data bag is defined using JSON. chef-solo will look for data bags in /var/chef/data_bags, but this location can be modified by changing the setting in solo.rb. For example, the following setting in solo.rb:

data_bag_path '/var/chef-solo/data_bags'

Create a data bag by creating folders. For example:

mkdir /var/chef-solo/data_bags

and:

mkdir /var/chef-solo/data_bags/admins

and then create a JSON file in that location:

{
  "id": "ITEM_NAME"
}

where the name of the file is the ITEM_NAME, for example:

/var/chef-solo/data_bags/admins/ITEM_NAME.json

Roles

A role is defined using JSON or the Ruby DSL. chef-solo will look for roles in /var/chef/roles, but this location can be modified by changing the setting for role_path in solo.rb. For example, the following setting in solo.rb:

role_path '/var/chef-solo/roles'

Role data looks like the following in JSON:

{
  "name": "test",
  "default_attributes": { },
  "override_attributes": { },
  "json_class": "Chef::Role",
  "description": "This is just a test role, no big deal.",
  "chef_type": "role",
  "run_list": [ "recipe[test]" ]
}

and like the following in the Ruby DSL:

name 'test'
description 'This is just a test role, no big deal.'
run_list 'recipe[test]'

and finally, JSON data passed to chef-solo:

{ 'run_list': 'role[test]' }

Environments

An environment is defined using JSON or the Ruby DSL. chef-solo will look for environments in /var/chef/environments, but this location can be modified by changing the setting for environment_path in solo.rb. For example, the following setting in solo.rb:

environment_path '/var/chef-solo/environments'

Environment data looks like the following in JSON:

{
  "name": "dev",
  "default_attributes": {
    "apache2": {
      "listen_ports": [
        "80",
        "443"
      ]
    }
  },
  "json_class": "Chef::Environment",
    "description": "",
    "cookbook_versions": {
    "couchdb": "= 11.0.0"
  },
  "chef_type": "environment"
  }

and like the following in the Ruby DSL:

name 'environment_name'
description 'environment_description'
cookbook OR cookbook_versions  'cookbook' OR 'cookbook' => 'cookbook_version'
default_attributes 'node' => { 'attribute' => [ 'value', 'value', 'etc.' ] }
override_attributes 'node' => { 'attribute' => [ 'value', 'value', 'etc.' ] }

chef-solo (executable)

The chef-solo executable is run as a command-line tool.

Options

This command has the following syntax:

chef-solo OPTION VALUE OPTION VALUE ...

This command has the following options:

-c CONFIG, --config CONFIG
The configuration file to use.
-d, --daemonize

Run the executable as a daemon. This option may not be used in the same command with the --[no-]fork option.

This option is only available on machines that run in UNIX or Linux environments. For machines that are running Microsoft Windows that require similar functionality, use the chef-client::service recipe in the chef-client cookbook: https://supermarket.chef.io/cookbooks/chef-client. This will install a chef-client service under Microsoft Windows using the Windows Service Wrapper.

-E ENVIRONMENT_NAME, --environment ENVIRONMENT_NAME
The name of the environment.
-f, --[no-]fork
Contain the chef-client run in a secondary process with dedicated RAM. When the chef-client run is complete, the RAM is returned to the master process. This option helps ensure that a chef-client uses a steady amount of RAM over time because the master process does not run recipes. This option also helps prevent memory leaks such as those that can be introduced by the code contained within a poorly designed cookbook. Use --no-fork to disable running the chef-client in fork node. Default value: --fork. This option may not be used in the same command with the --daemonize and --interval options.
-F FORMAT, --format FORMAT

The output format: doc (default) or min.

  • Use doc to print the progress of the chef-client run using full strings that display a summary of updates as they occur.
  • Use min to print the progress of the chef-client run using single characters.

A summary of updates is printed at the end of the chef-client run. A dot (.) is printed for events that do not have meaningful status information, such as loading a file or synchronizing a cookbook. For resources, a dot (.) is printed when the resource is up to date, an S is printed when the resource is skipped by not_if or only_if, and a U is printed when the resource is updated.

Other formatting options are available when those formatters are configured in the client.rb file using the add_formatter option.

--force-formatter
Show formatter output instead of logger output.
--force-logger
Show logger output instead of formatter output.
-g GROUP, --group GROUP
The name of the group that owns a process. This is required when starting any executable as a daemon.
-h, --help
Show help for the command.
-i SECONDS, --interval SECONDS
The frequency (in seconds) at which the chef-client runs. When the chef-client is run at intervals, --splay and --interval values are applied before the chef-client run. This option may not be used in the same command with the --[no-]fork option.
-j PATH, --json-attributes PATH

The path to a file that contains JSON data.

Use this option to define a run_list object. For example, a JSON file similar to:

"run_list": [
  "recipe[base]",
  "recipe[foo]",
  "recipe[bar]",
  "role[webserver]"
],

may be used by running chef-client -j path/to/file.json.

In certain situations this option may be used to update normal attributes.

Warning

Any other attribute type that is contained in this JSON file will be treated as a normal attribute. Setting attributes at other precedence levels is not possible. For example, attempting to update override attributes using the -j option:

{
  "name": "dev-99",
  "description": "Install some stuff",
  "override_attributes": {
    "apptastic": {
      "enable_apptastic": "false",
      "apptastic_tier_name": "dev-99.bomb.com"
    }
  }
}

will result in a node object similar to:

{
  "name": "maybe-dev-99",
  "normal": {
    "name": "dev-99",
    "description": "Install some stuff",
    "override_attributes": {
      "apptastic": {
        "enable_apptastic": "false",
        "apptastic_tier_name": "dev-99.bomb.com"
      }
    }
  }
}
-l LEVEL, --log_level LEVEL
The level of logging to be stored in a log file.
-L LOGLOCATION, --logfile c
The location of the log file. This is recommended when starting any executable as a daemon.
--legacy-mode

Cause the chef-client to not use chef local mode, but rather the original chef-solo mode. This is not recommended unless really required.

Removed in Chef Client 14.

--minimal-ohai
Run the Ohai plugins for name detection and resource/provider selection and no other Ohai plugins. Set to true during integration testing to speed up test cycles.
--[no-]color
View colored output. Default setting: --color.
-N NODE_NAME, --node-name NODE_NAME
The name of the node.
-o RUN_LIST_ITEM, --override-runlist RUN_LIST_ITEM
Replace the current run-list with the specified items.
-r RECIPE_URL, --recipe-url RECIPE_URL

The URL of the remote cookbook tar.gz file that you want to download.

In Chef Client 14, the short -r form will be removed, as it conflicts with the ability to specify a run list.

--run-lock-timeout SECONDS
The amount of time (in seconds) to wait for a chef-client lock file to be deleted. Default value: not set (indefinite). Set to 0 to cause a second chef-client to exit immediately.
-s SECONDS, --splay SECONDS
A random number between zero and splay that is added to interval. Use splay to help balance the load on the Chef server by ensuring that many chef-client runs are not occurring at the same interval. When the chef-client is run at intervals, --splay and --interval values are applied before the chef-client run.
-u USER, --user USER
The user that owns a process. This is required when starting any executable as a daemon.
-v, --version
The version of the chef-client.
-W, --why-run
Run the executable in why-run mode, which is a type of chef-client run that does everything except modify the system. Use why-run mode to understand why the chef-client makes the decisions that it makes and to learn more about the current and proposed state of the system.

Examples

Run chef-solo using solo.rb settings

$ chef-solo -c ~/chef/solo.rb

Use a URL

$ chef-solo -c ~/solo.rb -j ~/node.json -r http://www.example.com/chef-solo.tar.gz

The tar.gz is archived into the file_cache_path, and then extracted to cookbooks_path.

Use a directory

$ chef-solo -c ~/solo.rb -j ~/node.json

chef-solo will look in the solo.rb file to determine the directory in which cookbooks are located.

Use a URL for cookbook and JSON data

$ chef-solo -c ~/solo.rb -j http://www.example.com/node.json --recipe-url http://www.example.com/chef-solo.tar.gz

where --recipe-url corresponds to recipe_url and -j corresponds to json_attribs, both of which are configuration options in solo.rb.