I'm looking for a web-based admin panel that I can embedded in a custom linux-based embedded system. This should be similar to the admin interfaces commonly found on things like routers, where authorised users can login and configure various aspects of the linux system using a GUI. The panel must be configurable/extensible so that it is possible to add a new page/feature to configure a specific part of the system. Ideally, the software would be free for both personal and commercial applications.
What is Webmin?
Webmin is a web-based interface for system administration for Unix. Using any modern web browser, you can setup user accounts, Apache, DNS, file sharing and much more. Webmin removes the need to manually edit Unix configuration files like /etc/passwd, and lets you manage a system from the console or remotely. See the standard modules page for a list of all the functions built into Webmin.