Open Source Microsoft Active Directory Alternatives

The best open source alternative to Microsoft Active Directory is Zentyal. It's not free, so if you're looking for a free alternative, you could try Samba or Univention Corporate Server (UCS). If that doesn't suit you, our users have ranked more than 10 alternatives to Microsoft Active Directory and 14 is open source so hopefully you can find a suitable replacement. Other interesting open source alternatives to Microsoft Active Directory are FreeIPA, pGina Fork, 389 Directory Server and OpenLDAP.

filter to find the best alternatives

Microsoft Active Directory alternatives are mainly Linux Distros, but if you're looking for Mail Servers or Operating Systems you can filter on that. Other popular filters include Linux + Open Source. You can also filter by region, for example EU-based alternatives if you prefer software developed in the European Union. These are just examples - use the filter bar below to find more specific alternatives to Microsoft Active Directory.
Microsoft Active Directory iconMicrosoft Active Directory
  4
  • ...

Active Directory (AD) is a directory service that Microsoft developed for Windows domain networks and included in most Windows Server operating systems as a set of processes and services.

More about Microsoft Active Directory
More about Microsoft Active Directory
Microsoft Active Directory alternatives page was last updated Apr 8, 2025
Copy a direct link to this comment to your clipboard
  1. Zentyal icon

    Zentyal

     54 likes
    Copy a direct link to this comment to your clipboard

    Zentyal is a native Microsoft Active Directory implementation on Linux incorporating all the network services required in a small and medium business environment: Directory & Domain Server, Mail Server, Gateway and Infrastructure Server.

    26 Zentyal alternatives

    License model

    Application types

    Country of Origin

    • ES flagSpain
    • European Union flagEU

    Platforms

    • Linux
    Dashboard

    Zentyal Features

    1.  Gateway
    2.  Member Directory
    3.  Web interface

    Zentyal VS Microsoft Active Directory

     
    Comments about Zentyal as an Alternative to Microsoft Active Directory
    Arffeh
    Positive Dec 15, 2015
    0

    100% drop-in replacement, tried and tested by yours truely.

    pitou
    Positive May 12, 2017
    -2

    It's free and easy to use.

    Microsoft Active Directory Icon
    Zentyal icon

    • Most users think Zentyal is a great Microsoft Active Directory alternative.

    • Zentyal is the most popular Linux alternative to Microsoft Active Directory.

    • Zentyal is the most popular Open Source & commercial alternative to Microsoft Active Directory.

    • Zentyal is Paid and Open SourceMicrosoft Active Directory is Paid and Proprietary
  2. Samba icon

    Samba

     64 likes
    Copy a direct link to this comment to your clipboard

    Samba is the standard Windows interoperability suite of programs for Linux and Unix.

    14 Samba alternatives

    License model

    • Free • Open Source

    Country of Origin

    • US flagUnited States

    Platforms

    • Mac
    • Linux
    • BSD

    Samba Features

    1.  Filesystem

    Samba VS Microsoft Active Directory

     
    Comments about Samba as an Alternative to Microsoft Active Directory
    Guest
    Negative Apr 8, 2025
    0

    Samba's main prupose is usage of SMB protocol on linux computers than managing ones through a LDAP

    Guest
    Positive Nov 12, 2019
    2

    It's literally a reimplementation of AD on Linux. Samba has been around for many years and is trusted by thousands of admins to provide seamless Windows interoperability.

    Microsoft Active Directory Icon
    Samba icon

    • Most users think Samba is a great Microsoft Active Directory alternative.

    • Samba is the most popular Mac alternative to Microsoft Active Directory.

    • Samba is the most popular free alternative to Microsoft Active Directory.

    • Samba is Free and Open SourceMicrosoft Active Directory is Paid and Proprietary
  4. Univention Corporate Server (UCS) icon

    Univention Corporate Server (UCS)

     33 likes
    Copy a direct link to this comment to your clipboard

    UCS is an open platform for central identity & access management, IT management, and active directory, with a web portal for easy access to applications.

    95 Univention Corporate Server (UCS) alternatives

    License model

    • Freemium • Open Source

    Application types

    Country of Origin

    • DE flagGermany
    • European Union flagEU

    Platforms

    • Online
    • Software as a Service (SaaS)
    • Self-Hosted
    • Kubernetes
    Univention App Center

    Univention Corporate Server (UCS) Features

    1.  DHCP Server
    2.  Single Sign-On
    3.  Based on Debian
    4.  ARM support
    5.  Active Directory Migration
    6.  Multi-Factor Authentication (MFA)
    7. Microsoft Active Directory icon  Active Directory integration
    8.  SAML Single Sign-On

    Univention Corporate Server (UCS) VS Microsoft Active Directory

     
    Comments about Univention Corporate Server (UCS) as an Alternative to Microsoft Active Directory
    Guest
    Positive Jul 21, 2019
    0

    it works flawless and it's free as long you don't need commercial support. Companies can get professional support from UCS or UCS Partners. It is the most complete alternative to MS ADS.

    Microsoft Active Directory Icon
    Univention Corporate Server (UCS) icon

    • Almost everyone thinks Univention Corporate Server (UCS) is a great Microsoft Active Directory alternative.

    • Univention Corporate Server (UCS) is the most popular Web-based, SaaS & Self-Hosted alternative to Microsoft Active Directory.

    • Univention Corporate Server (UCS) is Freemium and Open SourceMicrosoft Active Directory is Paid and Proprietary
  5. FreeIPA icon

    FreeIPA

     13 likes
    Copy a direct link to this comment to your clipboard

    FreeIPA is an integrated security information management solution combining Linux (Fedora), 389 Directory Server, MIT Kerberos, NTP, DNS, Dogtag (Certificate System). It consists of a web interface and command-line administration tools.

    19 FreeIPA alternatives

    License model

    • Free • Open Source

    Country of Origin

    • US flagUnited States

    Platforms

    • Linux
    Using the authconfig utility to configure LDAP and Kerberos

    FreeIPA Features

    1.  DNS Server
    2.  LDAP Services
    3.  Kerberos
    4.  Web interface

    FreeIPA VS Microsoft Active Directory

     
    Comments about FreeIPA as an Alternative to Microsoft Active Directory
    soyatam443
    Negative Dec 9, 2023
    0

    They explicitly state that they don't intend to be a drop in replacement for active directory.

    Guest
    Positive Mar 12, 2020
    0

    not only completely free its the only one i implimented and joined linux hosts to it. all the rest failed to deliver.

    Microsoft Active Directory Icon
    FreeIPA icon

    • Most users think FreeIPA is a great Microsoft Active Directory alternative.

    • FreeIPA is Free and Open SourceMicrosoft Active Directory is Paid and Proprietary
  6. pGina Fork icon

    pGina Fork

     3 likes
    Copy a direct link to this comment to your clipboard

    pGina is a replacement for the default Windows Credential Provider. Through plugins, pGina allows you to configure the login process from authentication and authorization through Radius, SSH, Kerberos, POP, IMAP,... remote servers.

    4 pGina Fork alternatives

    License model

    • Free • Open Source

    Platforms

    • Windows
    pGina Fork screenshot 1

    pGina Fork Features

    1.  Kerberos
    2.  SSH
    3.  IMAP Support

    pGina Fork VS Microsoft Active Directory

     

    • pGina Fork is the most popular Windows alternative to Microsoft Active Directory.

    • pGina Fork is Free and Open SourceMicrosoft Active Directory is Paid and Proprietary
  7. 389 Directory Server icon

    389 Directory Server

     4 likes
    Copy a direct link to this comment to your clipboard

    Enterprise-class open source Linux LDAP server. Hardened by real-world use, full-featured, supports multi-master replication. 389 DS can be downloaded for free and set up in less than an hour using the graphical console.

    License model

    • Free • Open Source

    Country of Origin

    • US flagUnited States

    Platforms

    • Linux
    • CentOS
    • Fedora

    389 Directory Server VS Microsoft Active Directory

     
  9. OpenLDAP icon

    OpenLDAP

     9 likes
    Copy a direct link to this comment to your clipboard

    OpenLDAP Software is an open source implementation of the Lightweight Directory Access Protocol.

    15 OpenLDAP alternatives

    License model

    • Free • Open Source

    Platforms

    • Mac
    • Linux
    • BSD
    OpenLDAP screenshot 1

    OpenLDAP VS Microsoft Active Directory

     
  10. GLAuth icon

    GLAuth

     1 like
    Copy a direct link to this comment to your clipboard

    Go-lang LDAP Authentication (GLAuth) is a secure, easy-to-use, LDAP server with configurable backends.

    License model

    • Free • Open Source

    Platforms

    • Linux

    GLAuth VS Microsoft Active Directory

     
  11. RazDC icon

    RazDC

     1 like
    Copy a direct link to this comment to your clipboard

    It's an active directory replacement built on CentOS + Samaba4. Includes support for Directory, DNS, DCHP, and NTP type services.

    License model

    • Free • Open Source

    Platforms

    • Linux
    • Self-Hosted
    Color Pallet

    RazDC VS Microsoft Active Directory

     
9 of 14 Microsoft Active Directory alternatives