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Setting up Knife

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The knife command line tool must be configured to communicate with the Chef Infra Server as well as any other infrastructure within your organization. This is done initially during the workstation setup, but subsequent modifications can be made using the config.rb configuration file.

config.rb Configuration File

Knife is configured using a config.rb configuration, which contains configuration for both the knife command line tool as well as any installed knife plugins. See config.rb for a complete list of configuration options in the config.rb file.

Load Path Priority

The config.rb file is loaded every time the knife command is invoked using the following load order:

  • From a specified location given the --config flag
  • From a specified location given the $KNIFE_HOME environment variable, if set
  • From a config.rb file within the current working directory, e.g., ./config.rb
  • From a config.rb file within a .chef directory in the current working directory, e.g., ./.chef/config.rb
  • From a config.rb file within a .chef directory located one directory above the current working directory, e.g., ../.chef/config.rb
  • From ~/.chef/config.rb (macOS and Linux platforms) or c:\Users\<username>\.chef (Microsoft Windows platform)


When running Microsoft Windows, the config.rb file is located at %HOMEDRIVE%:%HOMEPATH%\.chef (e.g. c:\Users\<username>\.chef). If this path needs to be scripted, use %USERPROFILE%\chef-repo\.chef.

config.rb Configuration Within a Chef Repository

The config.rb configuration can include arbitrary Ruby code to extend configuration beyond static values. This can be used to load environmental variables from the workstation. This makes it possible to write a single config.rb file that can be used by all users within your organization. This single file can also be checked into your chef-repo, allowing users to load different config.rb files based on which chef-repo they execute the commands from. This can be especially useful when each chef-repo points to a different chef server or organization.

Example config.rb:

current_dir = File.dirname(__FILE__)
  user = ENV['CHEF_USER'] || ENV['USER']
  node_name                user
  client_key               "#{ENV['HOME']}/chef-repo/.chef/#{user}.pem"
  chef_server_url          "{ENV['ORGNAME']}"
  syntax_check_cache_path  "#{ENV['HOME']}/chef-repo/.chef/syntax_check_cache"
  cookbook_path            ["#{current_dir}/../cookbooks"]
  cookbook_copyright       "Your Company, Inc."
  cookbook_license         "Apache-2.0"
  cookbook_email           ""

  # Amazon AWS
  knife[:aws_access_key_id] = ENV['AWS_ACCESS_KEY_ID']
  knife[:aws_secret_access_key] = ENV['AWS_SECRET_ACCESS_KEY']

Generating a config.rb File

The knife command knife configure can be used to generate your initial config.rb configuration file in your home directory. See knife configure for details.

Knife Profiles

Profile Support since Chef 13.7

Knife profiles provide an alternative to using the config.rb files for configuring your knife client. This makes it easier to switch knife between multiple Chef Infra Servers or between multiple organizations on the same Chef Infra Server. Configure knife profiles by adding them to the .chef/credentials file in your home directory on your workstation. The credentials file is TOML formatted. Each profile is listed as a separate ‘table’ name of your choice, and is followed by key-value pairs. The keys correspond to any setting permitted in the config.rb file.

File paths, such as client_key or validator_key, will be relative to ~/.chef unless absolute paths are given. Clients can be identified with either node_name or client_name, with client_name being preferred.

Credentials for use with Target Mode (e.g. chef-client --target can also be stored as a separate profile in the credentials file. The name of the profile should match the DNS name of the target, and must be surrounded by single quotes when the name contains a period. For example: ['']. Keys that are valid configuration options will be passed to train, such as port.

# Example .chef/credentials file
node_name = "barney"
client_key = "barney_rubble.pem"
chef_server_url = ""

# a 'config context' such as knife can be is configured as a separate table
ssh_user = 'ubuntu' # this would have been knife[:ssh_user] in your config.rb
aws_profile = 'engineering'
use_sudo = true

# a client_key may also be specified inline as in this example
client_name = "admin"
client_key = """
validator_key = "test-validator.pem"
chef_server_url = ""

node_name = "brubble"
client_key = "preprod-brubble.pem"
chef_server_url = ""

user = "cisco"
password = "cisco"
enable_password = "cisco"

There are four ways to select which profile to use and are listed in priority order:

  1. Pass the --profile option to knife, e.g. knife node list --profile dev.
  2. Set the profile name in the CHEF_PROFILE environment variable.
  3. Write the profile name to the ~/.chef/context file.
  4. Otherwise, knife will use the ‘default’ profile.

Knife Config

knife config support since Chef 14.4

Your knife profiles can be managed with the knife config command.

You can list your profiles using the knife config list-profiles command, for example:

## Profile              Client   Key                          Server
 default             barney   ~/.chef/barney_rubble.pem
 dev                 admin    ~/.chef/admin.pem  
 web.preprod         brubble  ~/.chef/preprod-brubble.pem  btm      ~/.chef/btm.pem              https://localhost:443

The line that begins with the asterisk is the currently selected profile.

To change the current profile, run the knife config use-profile NAME command, which will write the profile name to the ~/.chef/context file.

Running knife config get-profile will print out the name of the currently selected profile.

If you need to troubleshoot any settings, you can verify the value that knife is using with the knife config get KEY command, for example:

knife config get chef_server_url
Loading from credentials file /home/barney/.chef/credentials

Setting Your Text Editor

Some knife commands, such as knife data bag edit, require that information be edited as JSON data using a text editor. For example, the following command:

knife data bag edit admins admin_name

will open up the text editor with data similar to:

  "id": "admin_name"

Changes to that file can then be made:

  "id": "Justin C."
  "description": "I am passing the time by letting time pass over me ..."

The type of text editor that is used by knife can be configured by adding an entry to your config.rb file, or by setting an EDITOR environment variable. For example, to configure knife to open the vim text editor, add the following to your config.rb file:

knife[:editor] = "/usr/bin/vim"

When a Microsoft Windows file path is enclosed in a double-quoted string (" “), the same backslash character (\) that is used to define the file path separator is also used in Ruby to define an escape character. The config.rb file is a Ruby file; therefore, file path separators must be escaped. In addition, spaces in the file path must be replaced with ~1 so that the length of each section within the file path is not more than 8 characters. For example, if EditPad Pro is the text editor of choice and is located at the following path:

C:\\Program Files (x86)\EditPad Pro\EditPad.exe

the setting in the config.rb file would be similar to:

knife[:editor] = "C:\\Progra~1\\EditPa~1\\EditPad.exe"

One approach to working around the double- vs. single-quote issue is to put the single-quotes outside of the double-quotes. For example, for Notepad++:

knife[:editor] = '"C:\Program Files (x86)\Notepad++\notepad++.exe" -nosession -multiInst'

for Sublime Text:

knife[:editor] = '"C:\Program Files\Sublime Text 2\sublime_text.exe" --wait'

for TextPad:

knife[:editor] = '"C:\Program Files (x86)\TextPad 7\TextPad.exe"'

and for vim:

knife[:editor] = '"C:\Program Files (x86)\vim\vim74\gvim.exe"'

Using Quotes

The text editor command cannot include spaces that are not properly wrapped in quotes. The command can be entered with double quotes (” “) or single quotes (' ‘), but this should be done consistently as shown in the examples above.