---
layout: default
title: LDAP
parent: Authentication backends
grand_parent: Configuration
nav_order: 2
---

# LDAP

**Authelia** supports using a LDAP server as the users database.

## Configuration

Configuration of the LDAP backend is done as follows

```yaml
authentication_backend:
  disable_reset_password: false
  ldap:
    # The url to the ldap server. Scheme can be ldap:// or ldaps://
    url: ldap://127.0.0.1

    # Skip verifying the server certificate (to allow self-signed certificate).
    skip_verify: false

    # The base dn for every entries
    base_dn: dc=example,dc=com

    # The attribute holding the username of the user. This attribute is used to populate
    # the username in the session information. It was introduced due to #561 to handle case
    # insensitive search queries.
    # For you information, Microsoft Active Directory usually uses 'sAMAccountName' and OpenLDAP
    # usually uses 'uid'
    # Beware that this attribute holds the unique identifiers for the users binding the user and the configuration
    # stored in database. Therefore only single value attributes are allowed and the value
    # must never be changed once attributed to a user otherwise it would break the configuration
    # for that user. Technically, non-unique attributes like 'mail' can also be used but we don't recommend using
    # them, we instead advise to use the attributes mentioned above (sAMAccountName and uid) to follow
    # https://www.ietf.org/rfc/rfc2307.txt.
    username_attribute: uid
    
    # An additional dn to define the scope to all users
    additional_users_dn: ou=users
    
    # The users filter used in search queries to find the user profile based on input filled in login form.
    # Various placeholders are available to represent the user input and back reference other options of the configuration:
    # - {input} is a placeholder replaced by what the user inputs in the login form. 
    # - {username_attribute} is a placeholder replaced by what is configured in `username_attribute`.
    # - {mail_attribute} is a placeholder replaced by what is configured in `mail_attribute`.
    # - DON'T USE - {0} is an alias for {input} supported for backward compatibility but it will be deprecated in later versions, so please don't use it.
    #
    # Recommended settings are as follows:
    # - Microsoft Active Directory: (&({username_attribute}={input})(objectCategory=person)(objectClass=user))
    # - OpenLDAP: (&({username_attribute}={input})(objectClass=person))' or '(&({username_attribute}={input})(objectClass=inetOrgPerson))
    #
    # To allow sign in both with username and email, one can use a filter like
    # (&(|({username_attribute}={input})({mail_attribute}={input}))(objectClass=person))
    users_filter: (&({username_attribute}={input})(objectClass=person))
    
    # An additional dn to define the scope of groups
    additional_groups_dn: ou=groups
    
    # The groups filter used in search queries to find the groups of the user.
    # - {input} is a placeholder replaced by what the user inputs in the login form.
    # - {username} is a placeholder replace by the username stored in LDAP (based on `username_attribute`).
    # - {dn} is a matcher replaced by the user distinguished name, aka, user DN.
    # - {username_attribute} is a placeholder replaced by what is configured in `username_attribute`.
    # - {mail_attribute} is a placeholder replaced by what is configured in `mail_attribute`.
    # - DON'T USE - {0} is an alias for {input} supported for backward compatibility but it will be deprecated in later versions, so please don't use it.
    # - DON'T USE - {1} is an alias for {username} supported for backward compatibility but it will be deprecated in later version, so please don't use it.
    groups_filter: (&(member={dn})(objectclass=groupOfNames))
    
    # The attribute holding the name of the group
    group_name_attribute: cn
    
    # The attribute holding the mail address of the user
    mail_attribute: mail
    
    # The username and password of the admin user. If multiple email addresses are defined for a user, only the first
    # one returned by the LDAP server is used.
    user: cn=admin,dc=example,dc=com
    
    # This secret can also be set using the env variables AUTHELIA_AUTHENTICATION_BACKEND_LDAP_PASSWORD
    password: password
```

The user must have an email address in order for Authelia to perform
identity verification when password reset request is initiated or
when a second factor device is registered.

## Important notes

Users must be uniquely identified by an attribute, this attribute must obviously contain a single value and
be guaranteed by the administrator to be unique. If multiple users have the same value, Authelia will simply
fail authenticating the user and display an error message in the logs.

In order to avoid such problems, we highly recommended you follow https://www.ietf.org/rfc/rfc2307.txt by using
`sAMAccountName` for Microsoft Active Directory and `uid` for other implementations as the attribute holding the
unique identifier for your users.