Integrate LDAP with GitLab

Tier: Free, Premium, Ultimate Offering: Self-managed

GitLab integrates with LDAP - Lightweight Directory Access Protocol to support user authentication.

This integration works with most LDAP-compliant directory servers, including:

  • Microsoft Active Directory.
  • Apple Open Directory.
  • Open LDAP.
  • 389 Server.
note
GitLab does not support Microsoft Active Directory Trusts.

Users added through LDAP:

  • Usually use a licensed seat.
  • Can authenticate with Git using either their GitLab username or their email and LDAP password, even if password authentication for Git is disabled.

The LDAP distinguished name (DN) is associated with existing GitLab users when:

  • The existing user signs in to GitLab with LDAP for the first time.
  • The LDAP email address is the primary email address of an existing GitLab user. If the LDAP email attribute isn’t found in the GitLab user database, a new user is created.

If an existing GitLab user wants to enable LDAP sign-in for themselves, they should:

  1. Check that their GitLab email address matches their LDAP email address.
  2. Sign in to GitLab by using their LDAP credentials.

Security

GitLab verifies if a user is still active in LDAP.

Users are considered inactive in LDAP when they:

  • Are removed from the directory completely.
  • Reside outside the configured base DN or user_filter search.
  • Are marked as disabled or deactivated in Active Directory through the user account control attribute. This means attribute userAccountControl:1.2.840.113556.1.4.803 has bit 2 set.

To check if a user is active or inactive in LDAP, use the following PowerShell command and the Active Directory Module to check the Active Directory: 

Get-ADUser -Identity <username> -Properties userAccountControl | Select-Object Name, userAccountControl

GitLab checks LDAP users’ status:

  • When signing in using any authentication provider.
  • Once per hour for active web sessions or Git requests using tokens or SSH keys.
  • When performing Git over HTTP requests using LDAP username and password.
  • Once per day during User Sync.

If the user is no longer active in LDAP, they are:

  • Signed out.
  • Placed in an ldap_blocked status.
  • Unable to sign in using any authentication provider until they are reactivated in LDAP.

Security risks

You should only use LDAP integration if your LDAP users cannot:

  • Change their mail, email or userPrincipalName attributes on the LDAP server. These users can potentially take over any account on your GitLab server.
  • Share email addresses. LDAP users with the same email address can share the same GitLab account.

Configure LDAP

Prerequisites:

  • You must have an email address to use LDAP, regardless of whether or not you use that email address to sign in.

To configure LDAP, you edit the settings in a configuration file:

The file you edit differs depending on your GitLab setup:

Linux package (Omnibus)

  1. Edit /etc/gitlab/gitlab.rb: 

    gitlab_rails['ldap_enabled'] = true
gitlab_rails['ldap_servers'] = {
  'main' => {
    'label' => 'LDAP',
    'host' =>  'ldap.mydomain.com',
    'port' => 636,
    'uid' => 'sAMAccountName',
    'bind_dn' => 'CN=Gitlab,OU=Users,DC=domain,DC=com',
    'password' => '<bind_user_password>',
    'encryption' => 'simple_tls',
    'verify_certificates' => true,
    'timeout' => 10,
    'active_directory' => false,
    'user_filter' => '(employeeType=developer)',
    'base' => 'dc=example,dc=com',
    'lowercase_usernames' => 'false',
    'retry_empty_result_with_codes' => [80],
    'allow_username_or_email_login' => false,
    'block_auto_created_users' => false
  }
}

  2. Save the file and reconfigure GitLab: 

    sudo gitlab-ctl reconfigure
Helm chart (Kubernetes)

  1. Export the Helm values: 

    helm get values gitlab > gitlab_values.yaml

  2. Edit gitlab_values.yaml: 

    global:
  appConfig:
    ldap:
      servers:
        main:
          label: 'LDAP'
          host: 'ldap.mydomain.com'
          port: 636
          uid: 'sAMAccountName'
          bind_dn: 'CN=Gitlab,OU=Users,DC=domain,DC=com'
          password: '<bind_user_password>'
          encryption: 'simple_tls'
          verify_certificates: true
          timeout: 10
          active_directory: false
          user_filter: '(employeeType=developer)'
          base: 'dc=example,dc=com'
          lowercase_usernames: false
          retry_empty_result_with_codes: [80]
          allow_username_or_email_login: false
          block_auto_created_users: false

  3. Save the file and apply the new values: 

    helm upgrade -f gitlab_values.yaml gitlab gitlab/gitlab

For more information, see how to configure LDAP for a GitLab instance that was installed by using the Helm chart.

Docker

  1. Edit docker-compose.yml: 

    version: "3.6"
services:
  gitlab:
    image: 'gitlab/gitlab-ee:latest'
    restart: always
    hostname: 'gitlab.example.com'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        gitlab_rails['ldap_enabled'] = true
        gitlab_rails['ldap_servers'] = {
          'main' => {
            'label' => 'LDAP',
            'host' =>  'ldap.mydomain.com',
            'port' => 636,
            'uid' => 'sAMAccountName',
            'bind_dn' => 'CN=Gitlab,OU=Users,DC=domain,DC=com',
            'password' => '<bind_user_password>',
            'encryption' => 'simple_tls',
            'verify_certificates' => true,
            'timeout' => 10,
            'active_directory' => false,
            'user_filter' => '(employeeType=developer)',
            'base' => 'dc=example,dc=com',
            'lowercase_usernames' => 'false',
            'retry_empty_result_with_codes' => [80],
            'allow_username_or_email_login' => false,
            'block_auto_created_users' => false
          }
        }

  2. Save the file and restart GitLab: 

    docker compose up -d
Self-compiled (source)

  1. Edit /home/git/gitlab/config/gitlab.yml: 

    production: &base
  ldap:
    enabled: true
    servers:
      main:
        label: 'LDAP'
        host: 'ldap.mydomain.com'
        port: 636
        uid: 'sAMAccountName'
        bind_dn: 'CN=Gitlab,OU=Users,DC=domain,DC=com'
        password: '<bind_user_password>'
        encryption: 'simple_tls'
        verify_certificates: true
        timeout: 10
        active_directory: false
        user_filter: '(employeeType=developer)'
        base: 'dc=example,dc=com'
        lowercase_usernames: false
        retry_empty_result_with_codes: [80]
        allow_username_or_email_login: false
        block_auto_created_users: false

  2. Save the file and restart GitLab: 

    # For systems running systemd
sudo systemctl restart gitlab.target

# For systems running SysV init
sudo service gitlab restart

For more information about the various LDAP options, see the ldap setting in gitlab.yml.example.

After configuring LDAP, to test the configuration, use the LDAP check Rake task.

Basic configuration settings

The following basic settings are available:

Setting Required Type Description
label Yes String A human-friendly name for your LDAP server. It is displayed on your sign-in page. Example: 'Paris' or 'Acme, Ltd.'
host Yes String IP address or domain name of your LDAP server. Ignored when hosts is defined. Example: 'ldap.mydomain.com'
port Yes Integer The port to connect with on your LDAP server. Ignored when hosts is defined. Example: 389 or 636 (for SSL)
uid Yes String The LDAP attribute that maps to the username that users use to sign in. Should be the attribute, not the value that maps to the uid. Does not affect the GitLab username (see attributes section). Example: 'sAMAccountName' or 'uid' or 'userPrincipalName'
base Yes String Base where we can search for users. Example: 'ou=people,dc=gitlab,dc=example' or 'DC=mydomain,DC=com'
encryption Yes String Encryption method (the method key is deprecated in favor of encryption). It can have one of three values: 'start_tls', 'simple_tls', or 'plain'. simple_tls corresponds to ‘Simple TLS’ in the LDAP library. start_tls corresponds to StartTLS, not to be confused with regular TLS. If you specify simple_tls, usually it’s on port 636, while start_tls (StartTLS) would be on port 389. plain also operates on port 389.
hosts No Array of strings and integers An array of host and port pairs to open connections. Each configured server should have an identical data set. This is not meant to configure multiple distinct LDAP servers, but to configure failover. Hosts are tried in the order they are configured. Example: [['ldap1.mydomain.com', 636], ['ldap2.mydomain.com', 636]]
bind_dn No String The full DN of the user you bind with. Example: 'america\momo' or 'CN=Gitlab,OU=Users,DC=domain,DC=com'
password No String The password of the bind user.
verify_certificates No Boolean Defaults to true. Enables SSL certificate verification if encryption method is start_tls or simple_tls. If set to false, no validation of the LDAP server’s SSL certificate is performed.
timeout No Integer Defaults to 10. Set a timeout, in seconds, for LDAP queries. This helps avoid blocking a request if the LDAP server becomes unresponsive. A value of 0 means there is no timeout.
active_directory No Boolean This setting specifies if LDAP server is Active Directory LDAP server. For non-AD servers it skips the AD specific queries. If your LDAP server is not AD, set this to false.
allow_username_or_email_login No Boolean Defaults to false. If enabled, GitLab ignores everything after the first @ in the LDAP username submitted by the user on sign-in. If you are using uid: 'userPrincipalName' on ActiveDirectory you must disable this setting, because the userPrincipalName contains an @.
block_auto_created_users No Boolean Defaults to false. To maintain tight control over the number of billable users on your GitLab installation, enable this setting to keep new users blocked until they have been cleared by an administrator .
user_filter No String Filter LDAP users. Follows the format of RFC 4515. GitLab does not support omniauth-ldap’s custom filter syntax. Examples of the user_filter field syntax:

- '(employeeType=developer)'
- '(&(objectclass=user)(|(samaccountname=momo)(samaccountname=toto)))'
lowercase_usernames No Boolean If enabled, GitLab converts the name to lower case.
retry_empty_result_with_codes No Array An array of LDAP query response code that attempt to retry the operation if the result/content is empty. For Google Secure LDAP, set this value to [80].

SSL configuration settings

You can configure SSL configuration settings under tls_options name/value pairs. The following settings are all optional:

Setting Description Examples
ca_file Specifies the path to a file containing a PEM-format CA certificate, for example, if you need an internal CA. '/etc/ca.pem'
ssl_version Specifies the SSL version for OpenSSL to use, if the OpenSSL default is not appropriate. 'TLSv1_1'
ciphers Specific SSL ciphers to use in communication with LDAP servers. 'ALL:!EXPORT:!LOW:!aNULL:!eNULL:!SSLv2'
cert Client certificate. '-----BEGIN CERTIFICATE----- <REDACTED> -----END CERTIFICATE -----'
key Client private key. '-----BEGIN PRIVATE KEY----- <REDACTED> -----END PRIVATE KEY -----'

The examples below illustrate how to set ca_file and ssl_version in tls_options:

Linux package (Omnibus)

  1. Edit /etc/gitlab/gitlab.rb: 

    gitlab_rails['ldap_enabled'] = true
gitlab_rails['ldap_servers'] = {
  'main' => {
    'label' => 'LDAP',
    'host' =>  'ldap.mydomain.com',
    'port' => 636,
    'uid' => 'sAMAccountName',
    'encryption' => 'simple_tls',
    'base' => 'dc=example,dc=com'
    'tls_options' => {
      'ca_file' => '/path/to/ca_file.pem',
      'ssl_version' => 'TLSv1_2'
    }
  }
}

  2. Save the file and reconfigure GitLab: 

    sudo gitlab-ctl reconfigure
Helm chart (Kubernetes)

  1. Export the Helm values: 

    helm get values gitlab > gitlab_values.yaml

  2. Edit gitlab_values.yaml: 

    global:
  appConfig:
    ldap:
      servers:
        main:
          label: 'LDAP'
          host: 'ldap.mydomain.com'
          port: 636
          uid: 'sAMAccountName'
          base: 'dc=example,dc=com'
          encryption: 'simple_tls'
          tls_options:
            ca_file: '/path/to/ca_file.pem'
            ssl_version: 'TLSv1_2'

  3. Save the file and apply the new values: 

    helm upgrade -f gitlab_values.yaml gitlab gitlab/gitlab

For more information, see how to configure LDAP for a GitLab instance that was installed by using the Helm chart.

Docker

  1. Edit docker-compose.yml: 

    version: "3.6"
services:
  gitlab:
    image: 'gitlab/gitlab-ee:latest'
    restart: always
    hostname: 'gitlab.example.com'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        gitlab_rails['ldap_enabled'] = true
        gitlab_rails['ldap_servers'] = {
          'main' => {
            'label' => 'LDAP',
            'host' =>  'ldap.mydomain.com',
            'port' => 636,
            'uid' => 'sAMAccountName',
            'encryption' => 'simple_tls',
            'base' => 'dc=example,dc=com',
            'tls_options' => {
              'ca_file' => '/path/to/ca_file.pem',
              'ssl_version' => 'TLSv1_2'
            }
          }
        }

  2. Save the file and restart GitLab: 

    docker compose up -d
Self-compiled (source)

  1. Edit /home/git/gitlab/config/gitlab.yml: 

    production: &base
  ldap:
    enabled: true
    servers:
      main:
        label: 'LDAP'
        host: 'ldap.mydomain.com'
        port: 636
        uid: 'sAMAccountName'
        encryption: 'simple_tls'
        base: 'dc=example,dc=com'
        tls_options:
          ca_file: '/path/to/ca_file.pem'
          ssl_version: 'TLSv1_2'

  2. Save the file and restart GitLab: 

    # For systems running systemd
sudo systemctl restart gitlab.target

# For systems running SysV init
sudo service gitlab restart

Attribute configuration settings

GitLab uses these LDAP attributes to create an account for the LDAP user. The specified attribute can be either:

  • The attribute name as a string. For example, 'mail'.
  • An array of attribute names to try in order. For example, ['mail', 'email'].

The user’s LDAP sign in is the LDAP attribute specified as uid.

All of the following LDAP attributes are optional. If you define these attributes, you must do so in an attributes hash.

Setting Description Examples
username Used in paths for the user’s own projects (for example, gitlab.example.com/username/project) and when mentioning them in issues, merge request and comments (for example, @username). If the attribute specified for username contains an email address, the GitLab username is part of the email address before the @. Defaults to the LDAP attribute specified as uid. ['uid', 'userid', 'sAMAccountName']
email LDAP attribute for user email. Defaults to ['mail', 'email', 'userPrincipalName'] ['mail', 'email', 'userPrincipalName']
name LDAP attribute for user display name. If name is blank, the full name is taken from the first_name and last_name. Defaults to 'cn'. Attributes 'cn', or 'displayName' commonly carry full names. Alternatively, you can force the use of first_name and last_name by specifying an absent attribute such as 'somethingNonExistent'.
first_name LDAP attribute for user first name. Used when the attribute configured for name does not exist. Defaults to 'givenName'. 'givenName'
last_name LDAP attribute for user last name. Used when the attribute configured for name does not exist. Defaults to 'sn'. 'sn'

LDAP sync configuration settings

Tier: Premium, Ultimate Offering: Self-managed

These LDAP sync configuration settings are optional, excluding group_base which required when external_groups is configured:

Setting Description Examples
group_base Base used to search for groups. All valid groups have this base as part of their DN. 'ou=groups,dc=gitlab,dc=example'
admin_group The CN of a group containing GitLab administrators. Not cn=administrators or the full DN. 'administrators'
external_groups An array of CNs of groups containing users that should be considered external. Not cn=interns or the full DN. ['interns', 'contractors']
sync_ssh_keys The LDAP attribute containing a user’s public SSH key. 'sshPublicKey' or false if not set
note
If Sidekiq is configured on a different server to the Rails server, you must add the LDAP configuration to every Sidekiq server as well for LDAP synchronisation to work.

Use multiple LDAP servers

Tier: Premium, Ultimate Offering: Self-managed

If you have users on multiple LDAP servers, you can configure GitLab to use them. To add additional LDAP servers:

  1. Duplicate the main LDAP configuration.
  2. Edit each duplicate configuration with the details of the additional servers.
    • For each additional server, choose a different provider ID, like main, secondary, or tertiary. Use lowercase alphanumeric characters. GitLab uses the provider ID to associate each user with a specific LDAP server.
    • For each entry, use a unique label value. These values are used for the tab names on the sign-in page.

The following example shows how to configure three LDAP servers with minimal configuration:

Linux package (Omnibus)

  1. Edit /etc/gitlab/gitlab.rb: 

    gitlab_rails['ldap_enabled'] = true
gitlab_rails['ldap_servers'] = {
  'main' => {
    'label' => 'GitLab AD',
    'host' =>  'ad.mydomain.com',
    'port' => 636,
    'uid' => 'sAMAccountName',
    'encryption' => 'simple_tls',
    'base' => 'dc=example,dc=com',
  },

  'secondary' => {
    'label' => 'GitLab Secondary AD',
    'host' =>  'ad-secondary.mydomain.com',
    'port' => 636,
    'uid' => 'sAMAccountName',
    'encryption' => 'simple_tls',
    'base' => 'dc=example,dc=com',
  },

  'tertiary' => {
    'label' => 'GitLab Tertiary AD',
    'host' =>  'ad-tertiary.mydomain.com',
    'port' => 636,
    'uid' => 'sAMAccountName',
    'encryption' => 'simple_tls',
    'base' => 'dc=example,dc=com',
  }
}

  2. Save the file and reconfigure GitLab: 

    sudo gitlab-ctl reconfigure
Helm chart (Kubernetes)

  1. Export the Helm values: 

    helm get values gitlab > gitlab_values.yaml

  2. Edit gitlab_values.yaml: 

    global:
  appConfig:
    ldap:
      servers:
        main:
          label: 'GitLab AD'
          host: 'ad.mydomain.com'
          port: 636
          uid: 'sAMAccountName'
          base: 'dc=example,dc=com'
          encryption: 'simple_tls'
        secondary:
          label: 'GitLab Secondary AD'
          host: 'ad-secondary.mydomain.com'
          port: 636
          uid: 'sAMAccountName'
          base: 'dc=example,dc=com'
          encryption: 'simple_tls'
        tertiary:
          label: 'GitLab Tertiary AD'
          host: 'ad-tertiary.mydomain.com'
          port: 636
          uid: 'sAMAccountName'
          base: 'dc=example,dc=com'
          encryption: 'simple_tls'

  3. Save the file and apply the new values: 

    helm upgrade -f gitlab_values.yaml gitlab gitlab/gitlab
Docker

  1. Edit docker-compose.yml: 

    version: "3.6"
services:
  gitlab:
    image: 'gitlab/gitlab-ee:latest'
    restart: always
    hostname: 'gitlab.example.com'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        gitlab_rails['ldap_enabled'] = true
        gitlab_rails['ldap_servers'] = {
          'main' => {
            'label' => 'GitLab AD',
            'host' =>  'ad.mydomain.com',
            'port' => 636,
            'uid' => 'sAMAccountName',
            'encryption' => 'simple_tls',
            'base' => 'dc=example,dc=com',
          },

          'secondary' => {
            'label' => 'GitLab Secondary AD',
            'host' =>  'ad-secondary.mydomain.com',
            'port' => 636,
            'uid' => 'sAMAccountName',
            'encryption' => 'simple_tls',
            'base' => 'dc=example,dc=com',
          },

          'tertiary' => {
            'label' => 'GitLab Tertiary AD',
            'host' =>  'ad-tertiary.mydomain.com',
            'port' => 636,
            'uid' => 'sAMAccountName',
            'encryption' => 'simple_tls',
            'base' => 'dc=example,dc=com',
          }
        }

  2. Save the file and restart GitLab: 

    docker compose up -d
Self-compiled (source)

  1. Edit /home/git/gitlab/config/gitlab.yml: 

    production: &base
  ldap:
    enabled: true
    servers:
      main:
        label: 'GitLab AD'
        host: 'ad.mydomain.com'
        port: 636
        uid: 'sAMAccountName'
        base: 'dc=example,dc=com'
        encryption: 'simple_tls'
      secondary:
        label: 'GitLab Secondary AD'
        host: 'ad-secondary.mydomain.com'
        port: 636
        uid: 'sAMAccountName'
        base: 'dc=example,dc=com'
        encryption: 'simple_tls'
      tertiary:
        label: 'GitLab Tertiary AD'
        host: 'ad-tertiary.mydomain.com'
        port: 636
        uid: 'sAMAccountName'
        base: 'dc=example,dc=com'
        encryption: 'simple_tls'

  2. Save the file and restart GitLab: 

    # For systems running systemd
sudo systemctl restart gitlab.target

# For systems running SysV init
sudo service gitlab restart

For more information about the various LDAP options, see the ldap setting in gitlab.yml.example.

This example results in a sign-in page with the following tabs:

  • GitLab AD.
  • GitLab Secondary AD.
  • GitLab Tertiary AD.

Set up LDAP user filter

To limit all GitLab access to a subset of the LDAP users on your LDAP server, first narrow the configured base. However, to further filter users if necessary, you can set up an LDAP user filter. The filter must comply with RFC 4515.

Linux package (Omnibus)

  1. Edit /etc/gitlab/gitlab.rb: 

    gitlab_rails['ldap_servers'] = {
  'main' => {
    'user_filter' => '(employeeType=developer)'
  }
}

  2. Save the file and reconfigure GitLab: 

    sudo gitlab-ctl reconfigure
Helm chart (Kubernetes)

  1. Export the Helm values: 

    helm get values gitlab > gitlab_values.yaml

  2. Edit gitlab_values.yaml: 

    global:
  appConfig:
    ldap:
      servers:
        main:
          user_filter: '(employeeType=developer)'

  3. Save the file and apply the new values: 

    helm upgrade -f gitlab_values.yaml gitlab gitlab/gitlab
Docker

  1. Edit docker-compose.yml: 

    version: "3.6"
services:
  gitlab:
    image: 'gitlab/gitlab-ee:latest'
    restart: always
    hostname: 'gitlab.example.com'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        gitlab_rails['ldap_servers'] = {
          'main' => {
            'user_filter' => '(employeeType=developer)'
          }
        }

  2. Save the file and restart GitLab: 

    docker compose up -d
Self-compiled (source)

  1. Edit /home/git/gitlab/config/gitlab.yml: 

    production: &base
  ldap:
    servers:
      main:
        user_filter: '(employeeType=developer)'

  2. Save the file and restart GitLab: 

    # For systems running systemd
sudo systemctl restart gitlab.target

# For systems running SysV init
sudo service gitlab restart

To limit access to the nested members of an Active Directory group, use the following syntax: 

(memberOf:1.2.840.113556.1.4.1941:=CN=My Group,DC=Example,DC=com)

For more information about LDAP_MATCHING_RULE_IN_CHAIN filters, see Search Filter Syntax.

Support for nested members in the user filter shouldn’t be confused with group sync nested groups support.

GitLab does not support the custom filter syntax used by OmniAuth LDAP.

Escape special characters in user_filter

The user_filter DN can contain special characters. For example:

  • A comma: 

    OU=GitLab, Inc,DC=gitlab,DC=com

  • Open and close brackets: 

    OU=GitLab (Inc),DC=gitlab,DC=com

These characters must be escaped as documented in RFC 4515.

  • Escape commas with \2C. For example: 

    OU=GitLab\2C Inc,DC=gitlab,DC=com

  • Escape open brackets with \28 and close brackets with \29. For example: 

    OU=GitLab \28Inc\29,DC=gitlab,DC=com

Enable LDAP username lowercase

Some LDAP servers, depending on their configuration, can return uppercase usernames. This can lead to several confusing issues such as creating links or namespaces with uppercase names.

GitLab can automatically lowercase usernames provided by the LDAP server by enabling the configuration option lowercase_usernames. By default, this configuration option is false.

Linux package (Omnibus)

  1. Edit /etc/gitlab/gitlab.rb: 

    gitlab_rails['ldap_servers'] = {
  'main' => {
    'lowercase_usernames' => true
  }
}

  2. Save the file and reconfigure GitLab: 

    sudo gitlab-ctl reconfigure
Helm chart (Kubernetes)

  1. Export the Helm values: 

    helm get values gitlab > gitlab_values.yaml

  2. Edit gitlab_values.yaml: 

    global:
  appConfig:
    ldap:
      servers:
        main:
         lowercase_usernames: true

  3. Save the file and apply the new values: 

    helm upgrade -f gitlab_values.yaml gitlab gitlab/gitlab
Docker

  1. Edit docker-compose.yml: 

    version: "3.6"
services:
  gitlab:
    image: 'gitlab/gitlab-ee:latest'
    restart: always
    hostname: 'gitlab.example.com'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        gitlab_rails['ldap_servers'] = {
          'main' => {
            'lowercase_usernames' => true
          }
        }

  2. Save the file and restart GitLab: 

    docker compose up -d
Self-compiled (source)

  1. Edit config/gitlab.yaml: 

    production:
  ldap:
    servers:
      main:
        lowercase_usernames: true

  2. Save the file and restart GitLab: 

    # For systems running systemd
sudo systemctl restart gitlab.target

# For systems running SysV init
sudo service gitlab restart

Disable LDAP web sign in

It can be useful to prevent using LDAP credentials through the web UI when an alternative such as SAML is preferred. This allows LDAP to be used for group sync, while also allowing your SAML identity provider to handle additional checks like custom 2FA.

When LDAP web sign in is disabled, users don’t see an LDAP tab on the sign-in page. This does not disable using LDAP credentials for Git access.

Linux package (Omnibus)

  1. Edit /etc/gitlab/gitlab.rb: 

    gitlab_rails['prevent_ldap_sign_in'] = true

  2. Save the file and reconfigure GitLab: 

    sudo gitlab-ctl reconfigure
Helm chart (Kubernetes)

  1. Export the Helm values: 

    helm get values gitlab > gitlab_values.yaml

  2. Edit gitlab_values.yaml: 

    global:
  appConfig:
    ldap:
      preventSignin: true

  3. Save the file and apply the new values: 

    helm upgrade -f gitlab_values.yaml gitlab gitlab/gitlab
Docker

  1. Edit docker-compose.yml: 

    version: "3.6"
services:
  gitlab:
    image: 'gitlab/gitlab-ee:latest'
    restart: always
    hostname: 'gitlab.example.com'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        gitlab_rails['prevent_ldap_sign_in'] = true

  2. Save the file and restart GitLab: 

    docker compose up -d
Self-compiled (source)

  1. Edit config/gitlab.yaml: 

    production:
  ldap:
    prevent_ldap_sign_in: true

  2. Save the file and restart GitLab: 

    # For systems running systemd
sudo systemctl restart gitlab.target

# For systems running SysV init
sudo service gitlab restart

Provide smart card authentication for GitLab

For more information on using smart cards with LDAP servers and GitLab, see Smart card authentication.

Use encrypted credentials

Instead of having the LDAP integration credentials stored in plaintext in the configuration files, you can optionally use an encrypted file for the LDAP credentials.

Prerequisites:

The encrypted configuration for LDAP exists in an encrypted YAML file. The unencrypted contents of the file should be a subset of the secret settings from your servers block in the LDAP configuration.

The supported configuration items for the encrypted file are:

  • bind_dn
  • password
Linux package (Omnibus)

  1. If initially your LDAP configuration in /etc/gitlab/gitlab.rb looked like: 

      gitlab_rails['ldap_servers'] = {
    'main' => {
      'bind_dn' => 'admin',
      'password' => '123'
    }
  }

  2. Edit the encrypted secret: 

    sudo gitlab-rake gitlab:ldap:secret:edit EDITOR=vim

  3. Enter the unencrypted contents of the LDAP secret: 

    main:
  bind_dn: admin
  password: '123'
  4. Edit /etc/gitlab/gitlab.rb and remove the settings for bind_dn and password.

  5. Save the file and reconfigure GitLab: 

    sudo gitlab-ctl reconfigure
Helm chart (Kubernetes)

Use a Kubernetes secret to store the LDAP password. For more information, read about Helm LDAP secrets.

Docker

  1. If initially your LDAP configuration in docker-compose.yml looked like: 

    version: "3.6"
services:
  gitlab:
    image: 'gitlab/gitlab-ee:latest'
    restart: always
    hostname: 'gitlab.example.com'
    environment:
      GITLAB_OMNIBUS_CONFIG: |
        gitlab_rails['ldap_servers'] = {
          'main' => {
            'bind_dn' => 'admin',
            'password' => '123'
          }
        }

  2. Get inside the container, and edit the encrypted secret: 

    sudo docker exec -t <container_name> bash
gitlab-rake gitlab:ldap:secret:edit EDITOR=vim

  3. Enter the unencrypted contents of the LDAP secret: 

    main:
  bind_dn: admin
  password: '123'
  4. Edit docker-compose.yml and remove the settings for bind_dn and password.

  5. Save the file and restart GitLab: 

    docker compose up -d
Self-compiled (source)

  1. If initially your LDAP configuration in /home/git/gitlab/config/gitlab.yml looked like: 

    production:
  ldap:
    servers:
      main:
        bind_dn: admin
        password: '123'

  2. Edit the encrypted secret: 

    bundle exec rake gitlab:ldap:secret:edit EDITOR=vim RAILS_ENVIRONMENT=production

  3. Enter the unencrypted contents of the LDAP secret: 

    main:
 bind_dn: admin
 password: '123'
  4. Edit /home/git/gitlab/config/gitlab.yml and remove the settings for bind_dn and password.

  5. Save the file and restart GitLab: 

    # For systems running systemd
sudo systemctl restart gitlab.target

# For systems running SysV init
sudo service gitlab restart

Updating LDAP DN and email

When an LDAP server creates a user in GitLab, the user’s LDAP DN is linked to their GitLab account as an identifier.

When a user tries to sign in with LDAP, GitLab tries to find the user using the DN saved on that user’s account.

  • If GitLab finds the user by the DN and the user’s email address:
    • Matches the GitLab account’s email address, GitLab does not take any further action.
    • Has changed, GitLab updates its record of the user’s email to match the one in LDAP.
  • If GitLab cannot find a user by their DN, it tries to find the user by their email. If GitLab:
    • Finds the user by their email, GitLab updates the DN stored in the user’s GitLab account. Both values now match the information stored in LDAP.
    • Cannot find the user by their email address (both the DN and the email address have changed), see User DN and email have changed.

Disable anonymous LDAP authentication

GitLab doesn’t support TLS client authentication. Complete these steps on your LDAP server.

  1. Disable anonymous authentication.
  2. Enable one of the following authentication types:
    • Simple authentication.
    • Simple Authentication and Security Layer (SASL) authentication.

The TLS client authentication setting in your LDAP server cannot be mandatory and clients cannot be authenticated with the TLS protocol.

Users deleted from LDAP

Users deleted from the LDAP server:

However, these users can continue to use Git with SSH until the next time the LDAP check cache runs.

To delete the account immediately, you can manually block the user.

Update user email addresses

Email addresses on the LDAP server are considered the source of truth for users when LDAP is used to sign in.

Updating user email addresses must be done on the LDAP server that manages the user. The email address for GitLab is updated either:

  • When the user next signs in.
  • When the next user sync is run.

The updated user’s previous email address becomes the secondary email address to preserve that user’s commit history.

You can find more details on the expected behavior of user updates in our LDAP troubleshooting section.

Google Secure LDAP

Google Cloud Identity provides a Secure LDAP service that can be configured with GitLab for authentication and group sync. See Google Secure LDAP for detailed configuration instructions.

Synchronize users and groups

For more information on synchronizing users and groups between LDAP and GitLab, see LDAP synchronization.

Move from LDAP to SAML

  1. Add SAML configuration to:

  2. Optional. Disable the LDAP auth from the sign-in page.

  3. Optional. To fix issues with linking users, you can first remove those users’ LDAP identities.

  4. Confirm that users are able to sign in to their accounts. If a user cannot sign in, check if that user’s LDAP is still there and remove it if necessary. If this issue persists, check the logs to identify the problem.

  5. In the configuration file, change:
    • omniauth_auto_link_user to saml only.
    • omniauth_auto_link_ldap_user to false.
    • ldap_enabled to false. You can also comment out the LDAP provider settings.

Troubleshooting

See our administrator guide to troubleshooting LDAP.