Chef Infra Client (executable)

Chef Infra Client is an agent that runs locally on every node that’s under management by Chef Infra Server. When Chef Infra Client runs, it performs all of the steps required for bringing a node into the expected state, including:

• Registering and authenticating the node with Chef Infra Server
• Synchronizing cookbooks from the Chef Infra Server to the node
• Compiling the resource collection by loading each of the required cookbooks, including recipes, attributes, and all other dependencies
• Taking the appropriate and required actions to configure the node based on recipes and attributes
• Reporting summary information on the run to Chef Automate

The Chef Infra Client executable is run as a command-line tool.

Options

This command has the following syntax:

chef-client OPTION VALUE OPTION VALUE ...

This command has the following options:

-A, --fatal-windows-admin-check

Cause a Chef Infra Client run to fail when the Chef Infra Client doesn’t have administrator privileges in Windows.

-c CONFIG, --config CONFIG

The configuration file to use.

--config-option OPTION

Overrides a single configuration option. Can be used to override multiple configuration options by adding another --config-option OPTION.

--chef-zero-host HOST

The host on which chef-zero is started.

--chef-zero-port PORT

The port on which chef-zero listens. If a port isn’t specified—individually, as range of ports, or from the chef_zero.port setting in the client.rb file—the Chef Infra Client will scan for ports between 8889-9999 and will pick the first port that’s available.

-d SECONDS, --daemonize SECONDS

Run the executable as a daemon. Use SECONDS to specify the number of seconds to wait before the first daemonized Chef Infra Client run. SECONDS is set to 0 by default. Left unset, the daemon uses the default --interval an --splay values.

This option is only available on machines that run in UNIX or Linux environments. For machines that are running 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 Infra Client service under Windows using the Windows Service Wrapper.

--delete-entire-chef-repo

This option deletes an entire repository. This option may only be used when running the Chef Infra Client in local mode, (--local-mode). This option requires --recipe-url to be specified.

--disable-config

Use to run the Chef Infra Client using default settings. This will prevent the normally-associated configuration file from being used. This setting should only be used for testing purposes and should never be used in a production setting.

-E ENVIRONMENT_NAME, --environment ENVIRONMENT_NAME

The name of the environment.

-f, --[no-]fork

Contain Chef Infra Client runs in a secondary process with dedicated RAM. When a Chef Infra Client run is complete, the RAM is returned to the master process. This option helps ensure that a Chef Infra Client uses a steady amount of RAM over time because the master process doesn’t 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 Chef Infra Client in fork node. Default value: --fork.

-F FORMAT, --format FORMAT

The output format: doc (default) or min.

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

A summary of updates is printed at the end of a Chef Infra 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 Chef Infra Client runs. When running Chef Infra Client at intervals, apply --splay and --interval values before a Chef Infra Client run. Default value: 1800.

-j PATH, --json-attributes PATH

The path to a file that contains JSON data. Used to setup the first client run. The attributes will persist on the Chef Infra Server for all future runs with option -j.

Run-lists

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.

Environments

Use this option to set the chef_environment value for a node.

Note

Any environment specified for chef_environment by a JSON file will take precedence over an environment specified by the --environment option when both options are part of the same command.

For example, run the following:

chef-client -j /path/to/file.json

where /path/to/file.json is similar to:

{
  "chef_environment": "pre-production"
}

This will set the environment for the node to pre-production.

All attributes are normal attributes

Any other attribute type that’s contained in this JSON file will be treated as a normal attribute. Setting attributes at other precedence levels isn’t 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"
          }
        }
      }
    }
    

Note

This has set the normal attribute node['override_attributes']['apptastic'].

Specify a policy

Use this option to use Policyfiles by specifying a JSON file that contains the following settings:

Setting	Description
policy_group	The name of a policy group that exists on the Chef Infra Server.
policy_name	The name of a policy, as identified by the name setting in a Policyfile.rb file.

For example:

{
  "policy_name": "appserver",
  "policy_group": "staging"
}

-k KEY_FILE, --client_key KEY_FILE

The location of the file that contains the client key. Default value: /etc/chef/client.pem.

-K KEY_FILE, --validation_key KEY_FILE

The location of the file that contains the key used when a Chef Infra Client is registered with a Chef Infra Server. A validation key is signed using the validation_client_name for authentication. Default value: /etc/chef/validation.pem.

-l LEVEL, --log_level LEVEL

The level of logging to be stored in a log file. Possible levels: auto (default), debug, error, fatal, info, trace, or warn. Default value: warn (when a terminal is available) or info (when a terminal isn’t available).

-L LOGLOCATION, --logfile LOGLOCATION

The location of the log file. This is recommended when starting any executable as a daemon. Default value: STDOUT.

--lockfile LOCATION

Use to specify the location of the lock file, which prevents multiple Chef Infra Client processes from converging at the same time.

--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.

--[no-]fips

Allows OpenSSL to enforce FIPS-validated security during a Chef Infra Client run.

--[no-]skip-cookbook-sync

Not recommended. Use cached cookbooks without overwriting local differences from the server. Useful for patching a set of cookbooks on a machine when iterating during development. This option can cause unanticipated behavior.

--[no-]listen

Run chef-zero in socketless mode. This is the default behavior on Chef Infra Client 13.1 and above.

-n NAME, --named-run-list NAME

The run-list associated with a Policyfile.

-N NODE_NAME, --node-name NODE_NAME

The unique identifier of the node.

-o RUN_LIST_ITEM, --override-runlist RUN_LIST_ITEM

Replace the current run-list with the specified items. This option won’t clear the list of cookbooks (and related files) that’s cached on the node. This option won’t persist node data at the end of the client run.

--once

Make only one Chef Infra Client run and cancel interval and splay options.

-P PID_FILE, --pid PID_FILE

The location in which a process identification number (pid) is saved. An executable, when started as a daemon, writes the pid to the specified file. Default value: /tmp/name-of-executable.pid.

--profile-ruby

Use the --profile-ruby option to dump a (large) profiling graph into /var/chef/cache/graph_profile.out. Use the graph output to help identify, and then resolve performance bottlenecks in a Chef Infra Client run. This option:

• Generates a large amount of data about a Chef Infra Client run.
• Has a dependency on the ruby-prof gem, which is packaged as part of Chef and Chef Workstation.
• Increases the amount of time required to complete a Chef Infra Client run.
• Should not be used in a production environment.

-r RUN_LIST_ITEM, --runlist RUN_LIST_ITEM

Permanently replace the current run-list with the specified run-list items.

-R, --enable-reporting

Enable Reporting, which performs data collection during a Chef Infra Client run.

RECIPE_FILE

The path to a recipe. For example, if a recipe file is in the current directory, use recipe_file.rb. This is typically used with the --local-mode option.

--recipe-url=RECIPE_URL

The location of a recipe when it exists at a URL. Use this option only when running Chef Infra Client with the --local-mode option.

--run-lock-timeout SECONDS

The amount of time (in seconds) to wait for a Chef Infra Client lock file to be deleted. Default value: not set (indefinite). Set to 0 to cause a second Chef Infra Client to exit immediately.

-s SECONDS, --splay SECONDS

A random number between zero and splay that’s added to interval. Use splay to help balance the load on the Chef Infra Server by ensuring that many Chef Infra Client runs aren’t occurring at the same interval. When running Chef Infra Client at intervals, apply --splay and --interval values before a Chef Infra Client run.

Changed in Chef Infra Client 12.0 to be applied before the Chef Infra Client run.

-S CHEF_SERVER_URL, --server CHEF_SERVER_URL

The URL for the Chef Infra Server.

-u USER, --user USER

The user that owns a process. This is required when starting any executable as a daemon.

-v, --version

The Chef Infra Client version.

-W, --why-run

Run the executable in why-run mode, which is a type of Chef Infra Client run that does everything except modify the system. Use why-run mode to understand why the Chef Infra Client makes the decisions that it makes and to learn more about the current and proposed state of the system.

-z, --local-mode

Run the Chef Infra Client in local mode. This allows all commands that work against the Chef Infra Server to also work against the local chef-repo.

Chef Infra Client Lock File

The Chef Infra Client uses a lock file to ensure that only one Chef Infra Client run is in progress at any time. A lock file is created at the start of a Chef Infra Client run and is deleted at the end of a Chef Infra Client run. A new Chef Infra Client run looks for the presence of a lock file and, if present, will wait for that lock file to be deleted. The location of the lock file can vary by platform.

• Use the lockfile setting in the client.rb file to specify non-default locations for the lock file. (The default location is typically platform-dependent and is recommended.)
• Use the run_lock_timeout setting in the client.rb file to specify the amount of time (in seconds) to wait for the lock file associated with an in-progress Chef Infra Client run to be deleted.

Run in Local Mode

Local mode is a way to run the Chef Infra Client against the chef-repo on a local machine as if it were running against the Chef Infra Server. Local mode relies on chef-zero, which acts as a lightweight instance of the Chef Infra Server. chef-zero reads and writes to the chef_repo_path, which allows all commands that normally work against the Chef Infra Server to be used against the local chef-repo.

Local mode doesn’t require a configuration file, instead it will look for a directory named /cookbooks and will set chef_repo_path to be just above that. (Local mode will honor the settings in a configuration file, if desired.) If the client.rb file isn’t found and no configuration file is specified, local mode will search for a config.rb file.

Local mode will store temporary and cache files under the <chef_repo_path>/.cache directory by default. This allows a normal user to run the Chef Infra Client in local mode without requiring root access.

About why-run Mode

why-run mode is a way to see what Chef Infra Client would have configured, had an actual Chef Infra Client run occurred. This approach is similar to the concept of “no-operation” (or “no-op”): decide what should be done, but then don’t actually do anything until it’s done right. This approach to configuration management can help identify where complexity exists in the system, where inter-dependencies may be located, and to verify that everything will be configured in the desired manner.

When why-run mode is enabled, a Chef Infra Client run will occur that does everything up to the point at which configuration would normally occur. This includes getting the configuration data, authenticating to the Chef Infra Server, rebuilding the node object, expanding the run-list, getting the necessary cookbook files, resetting node attributes, identifying the resources, and building the resource collection, but doesn’t include mapping each resource to a provider or configuring any part of the system.

When Chef Infra Client is run in why-run mode, certain assumptions are made:

• If the service resource can’t find the appropriate command to verify the status of a service, why-run mode will assume that the command would have been installed by a previous resource and that the service would not be running.
• For not_if and only_if properties, why-run mode will assume these are commands or blocks that are safe to run. These conditions aren’t designed to be used to change the state of the system, but rather to help facilitate idempotency for the resource itself. That said, it may be possible that these attributes are being used in a way that modifies the system state
• The closer the current state of the system is to the desired state, the more useful why-run mode will be. For example, if a full run-list is run against a fresh system, that run-list may not be completely correct on the first try, but also that run-list will produce more output than a smaller run-list

For example, the service resource can be used to start a service. If the action is :start, then the service will start if it’s not running and do nothing if it’s running. If a service is installed from a package, then Chef Infra Client can’t check to see if the service is running until after the package is installed. In that case, why-run mode will indicate what Chef Infra Client would do about the state of the service after installing a package. This is important because service actions often trigger notifications to other resources, so it’s important to know that these notifications are triggered correctly.

About chef-zero

chef-zero is a lightweight Chef Infra Server that runs in-memory on the local machine. This allows the Chef Infra Client to be run against the chef-repo as if it were running against the Chef Infra Server. chef-zero was originally a standalone tool; it’s enabled from within the Chef Infra Client by using the --local-mode option. chef-zero is useful for testing and validating the behavior of the Chef Infra Client, cookbooks, recipes, and run-lists before uploading that data to the actual Chef Infra Server.

Changed in Chef Infra Client 12.8, now chef-zero supports all Chef Server API version 12 endpoints, except /universe.

Use Encrypted Data Bags

Create an encrypted data bag for use with Chef Infra Client local mode

To generate an encrypted data bag item in a JSON file for use when Chef Infra Client is run in local mode (using the --local-mode option), enter:

knife data bag from file my_data_bag /path/to/data_bag_item.json -z --secret-file /path/to/encrypted_data_bag_secret

this will create an encrypted JSON file in:

data_bags/my_data_bag/data_bag_item.json

Run in FIPS Mode

Federal Information Processing Standards (FIPS) is a United States government computer security standard that specifies security requirements for cryptography. The current version of the standard is FIPS 140-2. Chef Infra Client can be configured to allow OpenSSL to enforce FIPS-validated security during a Chef Infra Client run. This will disable cryptography that’s explicitly disallowed in FIPS-validated software, including certain ciphers and hashing algorithms. Any attempt to use any disallowed cryptography will cause Chef Infra Client to throw an exception during a Chef Infra Client run.

Notes about FIPS:

• May be enabled for nodes running on Windows and Enterprise Linux platforms
• Should only be enabled for environments that require FIPS 140-2 compliance

Bootstrap a node using FIPS

knife bootstrap 192.0.2.0 -P vanilla -x root -r 'recipe[apt],recipe[xfs],recipe[vim]' --fips

which shows something similar to:

OpenSSL FIPS 140 mode enabled
...
192.0.2.0 Chef Infra Client finished, 12/12 resources updated in 78.942455583 seconds

Run as a Service

The Chef Infra Client can be run as a daemon. Use the Chef Infra Client cookbook to configure the Chef Infra Client as a daemon. Add the default recipe to a node’s run-list, and then use attributes in that cookbook to configure the behavior of the Chef Infra Client. For more information about these configuration options, see the Chef Infra Client cookbook repository on github.

When the Chef Infra Client is run as a daemon, the following signals may be used:

HUP

Use to reconfigure the Chef Infra Client.

INT

Use to terminate immediately without waiting for the current Chef Infra Client run to finish.

QUIT

Use to dump a stack trace, and continue to run.

TERM

Use to terminate but wait for the current Chef Infra Client run to finish, and then exit.

USR1

Use to wake up sleeping Chef Infra Client and trigger node convergence.

On Windows, both the HUP and QUIT signals aren’t supported.

Run with Elevated Privileges

Linux

On Linux, the following error sometimes occurs when the permissions used to run the Chef Infra Client are incorrect:

chef-client
[Tue, 29 Nov 2015 19:46:17 -0800] INFO: *** Chef 12.X.X ***
[Tue, 29 Nov 2015 19:46:18 -0800] WARN: Failed to read the private key /etc/chef/client.pem: #<Errno::EACCES: Permission denied - /etc/chef/client.pem>

This can be resolved by running the command as root. There are a few ways this can be done:

• Log in as root and then run the Chef Infra Client

• Use su to become the root user, and then run the Chef Infra Client. For example:

  su
  

  and then:

  chef-client
  

• Use the sudo utility

  sudo chef-client
  

• Give a user access to read /etc/chef and also the files accessed by the Chef Infra Client. This requires super user privileges and, as such, isn’t a recommended approach

Windows

On Windows, running without elevated privileges (when they are necessary) is an issue that fails silently. It will appear that Chef Infra Client completed its run successfully, but the changes will not have been made. When this occurs, do one of the following to run Chef Infra Client as the administrator:

• Log in to the administrator account. (This is not the same as an account in the administrator’s security group.)

• Run Chef Infra Client process from the administrator account while being logged into another account. Run the following command:

  runas /user:Administrator "cmd /C chef-client"
  

  This will prompt for the administrator account password.

• Open a command prompt by right-clicking on the command prompt application, and then selecting Run as administrator. After the command window opens, Chef Infra Client can be run as the administrator

Run as Non-root User

In large, distributed organizations the ability to modify the configuration of systems is sometimes segmented across teams, often with varying levels of access to those systems. For example, core application services may be deployed to systems by a central server provisioning team, and then developers on different teams build tooling to support specific applications. In this situation, a developer only requires limited access to machines and only needs to perform the operations that are necessary to deploy tooling for a specific application.

The default configuration of the Chef Infra Client assumes that it’s run as the root user. This affords the Chef Infra Client the greatest flexibility when managing the state of any object. However, the Chef Infra Client may be run as a non-root user—that’s, “run as a user with limited system privileges”—which can be useful when the objects on the system are available to other user accounts.

When the Chef Infra Client is run as a non-root user the Chef Infra Client can perform any action allowed to that user, as long as that action doesn’t also require elevated privileges (such as sudo or pbrun). Attempts to manage any object that requires elevated privileges will result in an error. For example, when the Chef Infra Client is run as a non-root user that’s unable to create or modify users, the user resource won’t work.

Set the Cache Path

To run a Chef Infra Client in non-root mode, add the file_cache_path setting to the client.rb file for the node that will run as the non-root user. Set the value of file_cache_path to be the home directory for the user that’s running the Chef Infra Client. For example:

file_cache_path '~/.chef/cache'

or:

file_cache_path File.join(File.expand_path('~'), '.chef', 'cache')

Elevate Commands

Another example of running the Chef Infra Client as a non-root user involves using resources to pass sudo commands as as an attribute on the resource. For example, the service resource uses a series of _command attributes (like start_command or stop_command), the package-based resources use the options attribute, and the script-based resources use the code attribute.

A command can be elevated similar to the following:

service 'apache2' do
  start_command 'sudo /etc/init.d/apache2 start'
  action :start
end

This approach can work well on a case-by-case basis. The challenge with this approach is often around managing the size of the /etc/sudoers file.

Run on IBM AIX

The Chef Infra Client may now be used to configure nodes that are running on the AIX platform, versions 7.1 (TL5 SP2 or higher, recommended) and 7.2. The service resource supports starting, stopping, and restarting services that are managed by System Resource Controller (SRC), as well as managing all service states with BSD-based init systems.

System Requirements

The Chef Infra Client has the same system requirements on the AIX platform as any other platform, with the following notes:

• Expand the file system on the AIX platform using chfs or by passing the -X flag to installp to automatically expand the logical partition (LPAR)
• The EN_US (UTF-8) character set should be installed on the logical partition before installing the Chef Infra Client

Install the Chef Infra Client on the AIX platform

The Chef Infra Client is distributed as a Backup File Format (BFF) binary and is installed on the AIX platform using the following command run as a root user:

# installp -aYgd chef-12.0.0-1.powerpc.bff all

Increase system process limits

The out-of-the-box system process limits for maximum process memory size (RSS) and number of open files are typically too low to run the Chef Infra Client on a logical partition (LPAR). When the system process limits are too low, the Chef Infra Client won’t be able to create threads. To increase the system process limits:

1. Validate that the system process limits haven’t already been increased.

2. If they haven’t been increased, run the following commands as a root user:

   chsec -f /etc/security/limits -s default -a "rss=-1"
   

   and then:

   chsec -f /etc/security/limits -s default -a "data=-1"
   

   and then:

   chsec -f /etc/security/limits -s default -a "nofiles=50000"
   

   Note

   The previous commands may be run against the root user, instead of default. For example:

   chsec -f /etc/security/limits -s root_user -a "rss=-1"
   

3. Reboot the logical partition (LPAR) to apply the updated system process limits.

When the system process limits are too low, an error is returned similar to:

Error Syncing Cookbooks:
==================================================================

Unexpected Error:
-----------------
ThreadError: can't create Thread: Resource temporarily unavailable

Install the UTF-8 character set

The Chef Infra Client uses the EN_US (UTF-8) character set. By default, the AIX base operating system doesn’t include the EN_US (UTF-8) character set and it must be installed before installing the Chef Infra Client. The EN_US (UTF-8) character set may be installed from the first disc in the AIX media or may be copied from /installp/ppc/*EN_US* to a location on the logical partition (LPAR). This topic assumes this location to be /tmp/rte.

Use smit to install the EN_US (UTF-8) character set. This ensures that any workload partitions (WPARs) also have UTF-8 applied.

Remember to point INPUT device/directory to /tmp/rte when not installing from CD.

1. From a root shell type:

   # smit lang
   

   A screen similar to the following is returned:

   Manage Language Environment
   
   Move cursor to desired item and press Enter.
   
   Change/Show Primary Language Environment
   Add Additional Language Environments
   Remove Language Environments
   Change/Show Language Hierarchy
   Set User Languages
   Change/Show Applications for a Language
   Convert System Messages and Flat Files
   
   F1=Help             F2=Refresh          F3=Cancel           F8=Image
   F9=Shell            F10=Exit            Enter=Do
   

2. Select Add Additional Language Environments and press Enter. A screen similar to the following is returned:

   Add Additional Language Environments
   
   Type or select values in entry fields. Press Enter AFTER making
   all desired changes.
   
   [Entry Fields]
   
   CULTURAL convention to install + LANGUAGE translation to
   install + INPUT device/directory for software [/dev/cd0] + EXTEND file
   systems if space needed? yes + WPAR Management
   
   Perform Operation in Global Environment yes + Perform
   Operation on Detached WPARs no + Detached WPAR Names
   [_all_wpars] + Remount Installation Device in WPARs
   yes + Alternate WPAR Installation Device []
   
   F1=Help F2=Refresh F3=Cancel F4=List F5=Reset F6=Command F7=Edit
   F8=Image F9=Shell F10=Exit Enter=Do
   

3. Cursor over the first two entries—CULTURAL convention to install and LANGUAGE translation to install—and use F4 to navigate through the list until UTF-8 English (United States) [EN_US] is selected. (EN_US is in capital letters!)

4. Press Enter to apply and install the language set.

Providers

The service resource has the following providers to support the AIX platform:

Enable a service on AIX using the mkitab command

The service resource doesn’t support using the :enable and :disable actions with resources that are managed using System Resource Controller (SRC). This is because System Resource Controller (SRC) does not have a standard mechanism for enabling and disabling services on system boot.

One approach for enabling or disabling services that are managed by System Resource Controller (SRC) is to use the execute resource to invoke mkitab, and then use that command to enable or disable the service.

The following example shows how to install a service:

execute "install #{node['chef_client']['svc_name']} in SRC" do
  command "mkssys -s #{node['chef_client']['svc_name']}
                  -p #{node['chef_client']['bin']}
                  -u root
                  -S
                  -n 15
                  -f 9
                  -o #{node['chef_client']['log_dir']}/client.log
                  -e #{node['chef_client']['log_dir']}/client.log -a '
                  -i #{node['chef_client']['interval']}
                  -s #{node['chef_client']['splay']}'"
  not_if "lssrc -s #{node['chef_client']['svc_name']}"
  action :run
end

and then enable it using the mkitab command:

execute "enable #{node['chef_client']['svc_name']}" do
  command "mkitab '#{node['chef_client']['svc_name']}:2:once:/usr/bin/startsrc
                  -s #{node['chef_client']['svc_name']} > /dev/console 2>&1'"
  not_if "lsitab #{node['chef_client']['svc_name']}"
end

Configuring a Proxy Server

See the proxies documentation for information on how to configure Chef Infra Client to use a proxy server.

Examples

Run the Chef Infra Client

sudo chef-client

Start a run when the Chef Infra Client is running as a daemon

A Chef Infra Client that’s running as a daemon can be woken up and started by sending the process a SIGUSR1. For example, to trigger a Chef Infra Client run on a machine running Linux:

sudo killall -USR1 chef-client

Setting the initial run-list using a JSON file

A node’s initial run-list is specified using a JSON file on the host system. When running Chef Infra Client as an executable, use the -j option to tell Chef Infra Client which JSON file to use. For example:

chef-client -j /etc/chef/file.json --environment _default

where file.json is similar to:

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

and where _default is the name of the environment that is assigned to the node.