Admidio

Admidio is a free, open-source web-based membership management system that provides member administration, event management, role-based access control, and organizational tools through a browser-based interface.

Key Features of Admidio:

• Open-source membership and user management system.
• Flexible role-based permission model for organizations.
• Event manager with participant registration and calendars.
• Member profiles, lists, and customizable fields.
• Internal messaging, photo albums, and document sharing.
• Multi-language support with an active plugin ecosystem.

Admidio Usage:

$ sudo su
$ cd /opt/admidio
$ systemctl restart apache2
$ systemctl status apache2

Access the Admidio interface: http://YOUR_SERVER_IP/

To check database credentials: $ cat /var/admidio/credentials.txt

Disclaimer:
Admidio is an open-source project maintained by the Admidio community. Users are responsible for configuring networking, database, authentication, access controls, and security before deployment.