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knife bootstrap

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A node is any physical, virtual, or cloud device that is configured and maintained by an instance of Chef Infra Client. Bootstrapping installs Chef Infra Client on a target system so that it can run as a client and sets the node up to communicate with a Chef Infra Server. There are two ways to do this:

  • Run the knife bootstrap command from a workstation.
  • Perform an unattended install to bootstrap from the node itself, without requiring SSH or WinRM connectivity.

Use the knife bootstrap subcommand to run a bootstrap operation that installs Chef Infra Client on the target system. The bootstrap operation must specify the IP address or FQDN of the target system.


  • Knife will copy the contents of the ~/.chef/client.d directory on your local workstation to the client.d directory on the device being bootstrapped with the knife bootstrap command. You can also set the client_d_dir option in the config.rb file to point to an arbitrary directory instead of ~/.chef/client.d, and the contents of that directory will be copied to the device being bootstrapped. All config files inside the client.d directory will get copied into the /etc/chef/client.d directory on the system being bootstrapped.
  • SSL certificates from an on-premises Chef Infra Server can be copied to the /trusted_certs_dir directory on your local workstation automatically by running knife ssl fetch. These certificates are used during knife operations to communicate with the Chef Infra Server.


This subcommand has the following syntax:

knife bootstrap FQDN_or_IP_ADDRESS (options)



Review the list of common options available to this (and all) knife subcommands and plugins.

General Connection Options

-U USERNAME, --connection-user USERNAME

Authenticate to the target host with this user account.

-P PASSWORD, --connection-password PASSWORD

Authenticate to the target host with this password.”

-p PORT, --connection-port PORT

The port on the target node to connect to.”

-o PROTOCOL, --connection-protocol PROTOCOL

The protocol to use to connect to the target node.

-W SECONDS, --max-wait SECONDS

The maximum time to wait for the initial connection to be established.

--session-timeout SECONDS

The number of seconds to wait for each connection operation to be acknowledged while running bootstrap.

WinRM Connection Options

--winrm-ssl-peer-fingerprint FINGERPRINT

SSL certificate fingerprint expected from the target.

-f CA_TRUST_PATH, --ca-trust-file CA_TRUST_PATH

The Certificate Authority (CA) trust file used for SSL transport


Do not verify the SSL certificate of the target node for WinRM.


Use SSL in the WinRM connection.

-w AUTH-METHOD, --winrm-auth-method AUTH-METHOD

The WinRM authentication method to use.


For WinRM basic authentication when using the ‘ssl’ auth method.


The Kerberos realm used for authentication.


The Kerberos service used for authentication.

SSH Connection Options

-G GATEWAY, --ssh-gateway GATEWAY

The SSH tunnel or gateway that is used to run a bootstrap action on a machine that is not accessible from the workstation.

--ssh-gateway-identity SSH_GATEWAY_IDENTITY

The SSH identity file used for gateway authentication.

-A, --ssh-forward-agent

Enable SSH agent forwarding.

-i IDENTITY_FILE, --ssh-identity-file IDENTITY_FILE

The SSH identity file used for authentication. Key-based authentication is recommended.

ssh_verify_host_key, --ssh-verify-host-key VALUE

Verify host key. Default is ‘always’

Chef Installation Options

--bootstrap-version VERSION

The version of Chef Infra Client to install.

--bootstrap-install-command COMMAND

Execute a custom installation command sequence for Chef Infra Client. This option may not be used in the same command with --bootstrap-curl-options or --bootstrap-wget-options.

--bootstrap-curl-options OPTIONS

Arbitrary options to be added to the bootstrap command when using cURL. This option may not be used in the same command with --bootstrap-install-command.

--bootstrap-wget-options OPTIONS

Arbitrary options to be added to the bootstrap command when using GNU Wget. This option may not be used in the same command with --bootstrap-install-command.

--bootstrap-preinstall-command COMMANDS

Custom commands to run before installing Chef Infra Client

--bootstrap-url URL

The URL to a custom installation script.

-m URL, --msi-url URL

Location of the Chef Infra Client MSI. The default templates will prefer to download from this location. The MSI will be downloaded from if not provided.


Execute a bootstrap operation with sudo.


Use to preserve the non-root user’s HOME environment.


Perform a bootstrap operation with sudo; specify the password with the -P (or --ssh-password) option.

-t TEMPLATE, --bootstrap-template TEMPLATE

The bootstrap template to use. This may be the name of a bootstrap template—chef-full for example—or it may be the full path to an Embedded Ruby (ERB) template that defines a custom bootstrap. Default value: chef-full, which installs Chef Infra Client using the Chef Infra installer on all supported platforms.

Proxy Options

--bootstrap-no-proxy NO_PROXY_URL_or_IP

A URL or IP address that specifies a location that should not be proxied during the bootstrap.

--bootstrap-proxy PROXY_URL

The proxy server for the node that is the target of a bootstrap operation.

--bootstrap-proxy-pass PROXY_PASS

The proxy authentication password for the node being bootstrapped.

--bootstrap-proxy-user PROXY_USER

The proxy authentication username for the node being bootstrapped.

Node Options

-N NAME, --node-name NAME

The name of the node.


This option is required for a validatorless bootstrap.

The name of the environment to be applied.

-r RUN_LIST, --run-list RUN_LIST

A comma-separated list of roles and/or recipes to be applied.

--secret SECRET

The encryption key that is used for values contained within a data bag item.

--secret-file FILE

The path to the file that contains the encryption key.


An Ohai hint to be set on the bootstrap target. See the Ohai documentation for more information. HINT_FILE is the name of the JSON file. HINT_NAME is the name of a hint in a JSON file. Use multiple --hint options to specify multiple hints.

-j JSON_ATTRIBS, --json-attributes JSON_ATTRIBS

A JSON string that is added to the first run of a Chef Infra Client.

--json-attribute-file FILE

A JSON file to be added to the first run of Chef Infra Client.


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

chef-vault Options

--bootstrap-vault-file VAULT_FILE

The path to a JSON file that contains a list of vaults and items to be updated.

--bootstrap-vault-item VAULT_ITEM

A single vault and item to update as vault:item.

--bootstrap-vault-json VAULT_JSON

A JSON string that contains a list of vaults and items to be updated. –bootstrap-vault-json ‘{ “vault1”: [“item1”, “item2”], “vault2”: “item2” }’

Key Verification Options


Use --no-host-key-verify to disable host key verification. Default setting: --host-key-verify.


Verify the SSL certificate on the Chef Infra Server. When true, Chef Infra Client always verifies the SSL certificate. When false, Chef Infra Client uses the value of ssl_verify_mode to determine if the SSL certificate requires verification. If this option is not specified, the setting for verify_api_cert in the configuration file is applied.

--node-ssl-verify-mode MODE

Set the verify mode for HTTPS requests. Options: none or peer.

Use none to do no validation of SSL certificates.

Use peer to do validation of all SSL certificates, including the Chef Infra Server connections, S3 connections, and any HTTPS remote_file resource URLs used in a Chef Infra Client run. This is the recommended setting.

Debug Options

-V -V

Run the initial Chef Infra Client run at the debug log-level (e.g. chef-client -l debug).

-V -V -V

Run the initial Chef Infra Client run at the trace log-level (e.g. chef-client -l trace).


See config.rb for more information about how to add certain knife options as settings in the config.rb file.

Validatorless Bootstrap

The ORGANIZATION-validator.pem is typically added to the .chef directory on the workstation. When a node is bootstrapped from that workstation, the ORGANIZATION-validator.pem is used to authenticate the newly-created node to the Chef Infra Server during the initial Chef Infra Client run. It is possible to bootstrap a node using the USER.pem file instead of the ORGANIZATION-validator.pem file. This is known as a “validatorless bootstrap”.

To create a node via the USER.pem file, simply delete the ORGANIZATION-validator.pem file on the workstation. For example:

rm -f /home/lamont/.chef/myorg-validator.pem

and then make the following changes in the config.rb file:

  • Remove the validation_client_name setting
  • Edit the validation_key setting to be something that isn’t a path to an existent ORGANIZATION-validator.pem file. For example: /nonexist.

As long as a USER.pem is also present on the workstation from which the validatorless bootstrap operation will be initiated, the bootstrap operation will run and will use the USER.pem file instead of the ORGANIZATION-validator.pem file.

When running a validatorless knife bootstrap operation, the output is similar to:

desktop% knife bootstrap -N \
  -E dev -r 'role[base]' -j '{ "foo": "bar" }' \
  --ssh-user vagrant --sudo
Node exists, overwrite it? (Y/N)
Client exists, overwrite it? (Y/N)
Creating new client for
Creating new node for
Connecting to Starting first Chef Client run...


The --node-name option is required for a validatorless bootstrap.


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 is 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.


Chef uses MD5 hashes to uniquely identify files that are stored on the Chef Infra Server. MD5 is used only to generate a unique hash identifier and is not used for any cryptographic purpose.

Notes about FIPS:

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

Bootstrap a node using FIPS

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

which shows something similar to:

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

Custom Templates

The default chef-full template uses the Chef installer. For most bootstrap operations, regardless of the platform on which the target node is running, using the chef-full distribution is the best approach for installing Chef Infra Client on a target node. In some situations, a custom template may be required.

For example, the default bootstrap operation relies on an Internet connection to get the distribution to the target node. If a target node cannot access the Internet, then a custom template can be used to define a specific location for the distribution so that the target node may access it during the bootstrap operation. The example below will show you how to create a bootstrap template that uses a custom artifact store for Chef packages and installation scripts, as well as a RubyGem mirror:

  1. A custom bootstrap template file must be located in a bootstrap/ directory, which is typically located within the ~/.chef/ directory on the local workstation. Navigate to the .chef directory, and create a bootstrap directory within it:

    mkdir bootstrap
  2. Move to the bootstrap directory and create a blank template file; this example will use template.erb for the template name:

    touch template.erb
  3. Still in the bootstrap directory, issue the following command to copy the chef-full configuration to your new template:

    find /opt/chef-workstation/embedded/lib/ruby -type f -name chef-full.erb -exec cat {} \; > template.erb

    This command searches for the chef-full template file under /opt/chef-workstation/embedded/lib/ruby, and then outputs the contents of the file to template.erb. If you used a different template file name, be sure to replace template.erb with the template file you created during the last step.

  4. Update template.erb to replace with the URL of an script on your artifact store:

    install_sh="<%= knife_config[:bootstrap_url] ? knife_config[:bootstrap_url] : "" %>"
  5. Still in your text editor, locate the following line near the bottom of your template.erb file:

    cat > /etc/chef/client.rb <<'EOP'
    <%= config_content %>

    Beneath it, add the following, replacing with the URL of your gem mirror:

    cat >> /etc/chef/client.rb <<'EOP'
    rubygems_url ""

    This appends the appropriate rubygems_url setting to the /etc/chef/client.rb file that is created during bootstrap, which ensures that your nodes use your internal gem mirror.

Bootstrap a Custom Template

You can use the --bootstrap-template option with the knife bootstrap subcommand to specify the name of your bootstrap template file:

knife bootstrap 123.456.7.8 -x username -P password --sudo --bootstrap-template "template"

Alternatively, you can use the knife[:bootstrap_template] option within config.rb to specify the template that knife bootstrap will use by default when bootstrapping a node. It should point to your custom template within the bootstrap directory:

knife[:bootstrap_template] = "#{current_dir}/bootstrap/template.erb"


The following examples show how to use this knife subcommand:

Bootstrap a node

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

which shows something similar to:

... Chef Infra Client finished, 12/12 resources updated in 78.942455583 seconds

Use knife node show to verify:

knife node show

which returns something similar to:

Node Name:
Environment: _default
Run List:    recipe[apt], recipe[xfs], recipe[vim]
Recipes:     apt, xfs, vim, apt::default, xfs::default, vim::default
Platform:    debian 10.0

Use an SSH password

knife bootstrap -x username -P PASSWORD --sudo

Use a file that contains a private key

knife bootstrap -x username -i ~/.ssh/id_rsa --sudo

Specify options when using cURL

knife bootstrap --bootstrap-curl-options "--proxy"

Specify options when using GNU Wget

knife bootstrap --bootstrap-wget-options "-e use_proxy=yes -e"

Specify a custom installation command sequence

knife bootstrap --bootstrap-install-command "curl -l | sudo bash -s --"