Installation of the Enterprise version is little different from that with the freeware version. The installer is graphical and wizard-based, and it's a very simple job of defining your disk partitions (or choosing "auto-partition" if you don't have extravagant requirements), selecting which software packages to install (you can pick individual server components such as databases, DNS, Windows file sharing, network file services, and so on, or you can do what we did and choose "everything") and hitting "Go". On our 1GHz Pentium-III test server the process of copying files took about 45 minutes, with the system prompting us to swap CDs from time to time. When the main installation had finished, you're asked to configure the X-Windows graphical user interface; this can be a bit fiddly but if your equipment is reasonably old then nine times out of ten it'll auto-detect your graphics card and monitor type. The GUI desktop looks rather like the one with the basic Red Hat product, with a few additional gizmos. There are plenty of graphical configuration tools for the various key server applications, such as the DNS (traditionally a pain to configure via text files), Samba (Windows file sharing), HTTP (Web) server and NFS file sharing systems – though this is in no way different from the freeware version, which gives you precisely the same tools if you select the "server" or "everything" options at install time. Integration with directory services using LDAP is also handled via a nice GUI interface, although you can choose to use Unix-type directory services such as NIS if you so desire. Add-ons
RHEL's download site has a few add-ons for the system that you can download either as individual packages or on a CD image. There are only a couple of dozen at the time of writing, including Red Hat-specific versions of the MySQL and PostgreSQL database systems and various Java runtime packages and development tools (the Eclipse IDE that's becoming increasingly popular at the moment). So just what does RHEL give you that the freeware version doesn't? In short, the stuff that many organisations need: stability and support. Whereas the freeware version (now distributed under the Fedora banner) is updated with great regularity and can be considered "bleeding edge", you get guarantees with the Enterprise version that new versions will be less frequent but tested to death; not only this, but you get the guarantee that the current version will be officially supported for at least five years, which can't be said about the free version. Then there's application support: the high-end commercial applications produced by big names like IBM, Oracle, Computer Associates and the like are labelled as compatible with Red Hat Enterprise, and you can guarantee that this will be the case; it can't be denied that even though something claims to be compatible with the non-Enterprise version, your server is much more at the mercy of some undiscovered kernel bug that crept in via one of several dozen new releases. Oh, and still on the subject of support, bear in mind that the Enterprise versions are the only ones that you can phone Red Hat and get support for (though bear in mind that AS is the only one for which you can buy 24x7, 1-hour response for). Finally, (but significantly) you do have those hardware-specific benefits that allow you to run the commercial versions (depending on which one you have) on something other than an x86 platform, with more than two processors, and with shedloads of memory.
If you don't need the formal support and you're not trying to run the thing on an IBM mainframe, go for the freeware version (now marketed under the Fedora banner). If you crave the reliability and formal support of a commercial product, go for Enterprise.