I installed Webmin from an RPM (Red Hat Package Manager), but you can also download a gzip'd tar file distribution. Webmin is a pure Perl application and requires at least Perl 5. Although default access is to root only, you can configure additional users and groups from the console.
A lengthy list of modules is included in the distribution, and you can begin managing systems immediately (see module list). Some modules, such as MySQL, are likely to require a bit of configuration to provide full access to management functions. But most system modules will be fully manageable out of the box. To enable full management of MySQL, it was only necessary to modify the login configuration. From that point on, I could perform queries as well as modify databases, tables and rows from Webmin. You can download new management modules or develop your own via the available API for custom applications.
Centrally manages every aspect of multiple Linux/Unix servers
Supports a plethora of operating systems
Menu system categorization of modules is not always intuitive
Some of the modules contain administration functions, such as file system back up and restore and complete BIND management, and I found them extremely useful. The only downside to the BIND management module is that you're still editing the core BIND files by hand. Basic configuration options and some advanced features, such as migrating a slave to a master, are available. But for basic modifications to the records, you're in text-edit mode using a standard HTML textbox. This is true of most modules when configuration files are involved.