Active Directory and LDAP¶

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The Chef server supports Active Directory and LDAP authentication, which enables users to log in to the Chef server using their corporate credentials.

Configure LDAP¶

The Chef server supports using Active Directory or LDAP for any user that has an email address in the LDAP directory. This allows those users to log in to the Chef server by using their corporate credentials instead of having a separate username and password.

Warning

The following attributes MUST be in the user LDAP record:

mail:
sAMAccountName: or uid:

The following attributes SHOULD be in the user LDAP record:

displayname:
givenname:
sn:
c:
l:

To configure the Chef server to use Active Directory or LDAP do the following:

Install the Chef management console (if it is not already).
Add the following settings to the /etc/opscode/chef-server.rb file. These settings must be added to the chef-server.rb file on each machine in the Chef server frontend deployment of a High Availability installation as well as on Chef servers in a standalone installation.
Warning

The following settings MUST be in the config file for LDAP authentication to Active Directory to work:
- base_dn
- bind_dn
- group_dn
- host
If those settings are missing, you will get authentication errors and be unable to proceed.
This configuration file has the following settings for ldap:
ldap['base_dn']
The root LDAP node under which all other nodes exist in the directory structure. For Active Directory, this is typically cn=users and then the domain. For example:
'OU=Employees,OU=Domain users,DC=example,DC=com'
Default value: nil.
ldap['bind_dn']
The distinguished name used to bind to the LDAP server. The user the Chef server will use to perform LDAP searches. This is often the administrator or manager user. This user needs to have read access to all LDAP users that require authentication. The Chef server must do an LDAP search before any user can log in. Many Active Directory and LDAP systems do not allow an anonymous bind. If anonymous bind is allowed, leave the bind_dn and bind_password settings blank. If anonymous bind is not allowed, a user with READ access to the directory is required. This user must be specified as an LDAP distinguished name similar to:
'CN=user,OU=Employees,OU=Domainuser,DC=example,DC=com'
Note

If you need to escape characters in a distinguished name, such as when using Active Directory, they must be escaped with a backslash escape character.
'CN=example\\user,OU=Employees,OU=Domainuser,DC=example,DC=com'
Default value: nil.
ldap['bind_password']
Legacy configuration for the password of the binding user. The password for the user specified by ldap['bind_dn']. Leave this value and ldap['bind_dn'] unset if anonymous bind is sufficient. Default value: nil. As of Chef server 12.14, this is no longer the preferred command.

Please use chef-server-ctl set-secret ldap bind_password from the Secrets Management commands.
$ chef-server-ctl set-secret ldap bind_password Enter ldap bind_password: (no terminal output) Re-enter ldap bind_password: (no terminal output)
Remove a set password via
$ chef-server-ctl remove-secret ldap bind_password
ldap['group_dn']
The distinguished name for a group. When set to the distinguished name of a group, only members of that group can log in. This feature filters based on the memberOf attribute and only works with LDAP servers that provide such an attribute. In OpenLDAP, the memberOf overlay provides this attribute. For example, if the value of the memberOf attribute is CN=abcxyz,OU=users,DC=company,DC=com, then use:
ldap['group_dn'] = 'CN=abcxyz,OU=users,DC=company,DC=com'
ldap['host']

The name (or IP address) of the LDAP server. The hostname of the LDAP or Active Directory server. Be sure the Chef server is able to resolve any host names. Default value: ldap-server-host.

ldap['login_attribute']

The LDAP attribute that holds the user’s login name. Use to specify the Chef server user name for an LDAP user. Default value: sAMAccountName.

ldap['port']

An integer that specifies the port on which the LDAP server listens. The default value is an appropriate value for most configurations. Default value: 389 or 636 when ldap['encryption'] is set to :simple_tls.

ldap['ssl_enabled']

Cause the Chef server to connect to the LDAP server using SSL. Default value: false. Must be false when ldap['tls_enabled'] is true.

Note

It’s recommended that you enable SSL for Active Directory.

Note

Previous versions of the Chef server used the ldap['ssl_enabled'] setting to first enable SSL, and then the ldap['encryption'] setting to specify the encryption type. These settings are deprecated.

ldap['system_adjective']

A descriptive name for the login system that is displayed to users in the Chef server management console. If a value like “corporate” is used, then the Chef management console user interface will display strings like “the corporate login server”, “corporate login”, or “corporate password.” Default value: AD/LDAP.

Warning

This setting is not used by the Chef server. It is used only by the Chef management console.

ldap['timeout']

The amount of time (in seconds) to wait before timing out. Default value: 60000.

ldap['tls_enabled']

Enable TLS. When enabled, communication with the LDAP server is done via a secure SSL connection on a dedicated port. When true, ldap['port'] is also set to 636. Default value: false. Must be false when ldap['ssl_enabled'] is true.

Note

Previous versions of the Chef server used the ldap['ssl_enabled'] setting to first enable SSL, and then the ldap['encryption'] setting to specify the encryption type. These settings are deprecated.
Note

If the chef-server.rb file does not exist, create a file called chef-server.rb and put it in the /etc/opscode/ directory.
Reconfigure the Chef server and the Chef management console (standalone and frontend group members

of a High Availabilty installation):
```
$ chef-server-ctl reconfigure
```

At this point, all users should be able to use their Active Directory or LDAP usernames and passwords to log in to the Chef server.

Test LDAP Connectivity¶

Use ldapsearch to test the ability of the Chef server to use Active Directory or LDAP. First, translate the Chef server LDAP settings into ldapsearch parameters:

Chef Server Setting	`ldapsearch` Parameter
`ldap['host']` and `ldap['port']`	`-H [HOST:PORT]`
`ldap['bind_dn']`	`-D [BIND_DN]`
`ldap['bind_password']`	`-W`; `ldapsearch` will prompt for this parameter
`ldap['base_dn']`	`-b [BASE_DN]`
`ldap['login_attribute']`	Defaults to `SAMAccountName`

And then from a front end machine (in a high availability or tiered configuration) or from the Chef server in a standalone configuration, run the following command. Be sure to replace the uppercase placeholders with the values for your organization:

$ ldapsearch -LLL -H ldap://HOST:PORT -b 'BASE_DN' -D 'BIND_DN' -W '(LOGIN_ATTRIBUTE=YOUR_LDAP_ACCOUNT_USERNAME)'

For example:

$ ldapsearch -LLL -H ldap://win-ad1.chef.co:389 -b 'OU=Employees,OU=Domain users,DC=opscodecorp,DC=com' -D 'CN=Robert Forster,OU=Employees,OU=Domain users,DC=opscodecorp,DC=com' -W '(sAMAccountName=rforster)'

Output similar to the following is returned:

$ ldapsearch -LLL -H ldap://win-ad1.chef.co:389 -b 'OU=Employees,OU=Domain users,DC=opscodecorp,DC=com' -D 'CN=Robert Forster,OU=Employees,OU=Domain users,DC=opscodecorp,DC=com' -W '(sAMAccountName=rforster)'
Enter LDAP Password:

dn: CN=Robert Forster,OU=Employees,OU=Domain users,DC=opscodecorp,DC=com
objectClass: top
objectClass: person
objectClass: organizationalPerson
objectClass: user
cn: Robert Forster
sn: Forster
c: 0
givenName: Robert
distinguishedName: CN=Robert Forster,OU=Employees,OU=Domain users,DC=opscodecorp,DC
 =com

Note

The ldapsearch command may need to be installed on the platform. It is not included as part of the Chef server package.