Keycloak - Open Source Identity and Access Management for modern Applications and Services.
NQE - CIFS/SMB based solutions for embedded / mobile markets.
Zentyal - Linux directory, domain, mail, gateway and infrastructure server for SMBs.
Samba - Samba serves as an open source alternative to the traditional domain controller offered by Microsoft.
OpenLDAP - OpenLDAP Software is an open source implementation of the Lightweight Directory Access Protocol.
NFS Manager - NFS Manager is a graphical user interface to control all built-in NFS features of Mac OS X.