After you choose an installation method (and, if you're installing via the network, after you configure networking information), the installation program prompts you to either install or upgrade (see Figure 15).
You usually install Red Hat Linux on a clean disk partition or set of partitions, or over another installation of Linux.
Please Note: Installing Red Hat Linux over another installation of Linux (including Red Hat Linux) does not preserve any information from the prior installation. Make sure you save any important files!
If you wish to perform a full install, choose Install, and skip to section 4.2.
The installation process for Red Hat Linux 5.0 includes the ability to upgrade from prior versions of Red Hat Linux (version 2.0 and later) which are based on RPM technology. Upgrading your system installs the modular 2.0.x kernel as well as updated versions of the packages which are currently installed on your machine. The upgrade process preserves existing configuration files by renaming them using a .rpmsave extension (e.g., sendmail.cf.rpmsave) and leaves a log telling what actions it took in /tmp/upgradelog. As software evolves, configuration file formats can change, so you should carefully compare your original configuration files to the new files before integrating your changes.
If you wish to upgrade your Red Hat Linux system, choose Upgrade.
Please Note: Some upgraded packages may require that other packages are also installed for proper operation. The upgrade procedure takes care of these dependencies, but it may need to install additional packages. You will be shown the names of the required packages, and you may then decide to install them or not.