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.
Integrates native Active Directory and all essential network services, including domain, mail, gateway, infrastructure, and security roles, for SMBs, offering web-based management, centralized authentication, file server, VPN, and firewall in a single Linux platform.
Samba is the standard Windows interoperability suite of programs for Linux and Unix.
UCS is an open platform for central identity & access management, IT management, and active directory, with a web portal for easy access to applications.
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.
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.
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.
OpenLDAP Software is an open source implementation of the Lightweight Directory Access Protocol.
It's an active directory replacement built on CentOS + Samaba4. Includes support for Directory, DNS, DCHP, and NTP type services.
ApacheDS™ is an extensible and embeddable directory server entirely written in Java, which has been certified LDAPv3 compatible by the Open Group. Besides LDAP it supports Kerberos 5 and the Change Password Protocol.
linuxmuster.net is a comprehensive complete solution for the operation of school IT infrastructure. It is developed by teachers and service providers for the special requirements of schools. When developing our solution, we try to keep some ...
OpenDJ is a directory server which implements a wide range of Lightweight Directory Access Protocol and related standards, including full compliance with LDAPv3 but also support for Directory Service Markup Language (DSMLv2).
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