Chapter 5. Planning for Installation on AMD64 and Intel 64 Systems
5.1. Upgrade or Install?
- Clean Install
- A clean install is performed by backing up all data from the system, formatting disk partitions, performing an installation of Red Hat Enterprise Linux from installation media, and then restoring any user data.
NoteThis is the recommended method for upgrading between major versions of Red Hat Enterprise Linux.
- In-Place Upgrade
- An in-place upgrade is a way of upgrading your system without removing the older version first. The procedure requires installing the migration utilities available for your system and running them as any other software. In Red Hat Enterprise Linux, the Preupgrade Assistant assesses your current system and identifies potential problems you might encounter during or after the upgrade. It also performs minor fixes and modifications to the system. The Red Hat Upgrade Tool utility downloads the packages and performs the actual upgrade. An in-place upgrade requires a lot of troubleshooting and planning and should only be done if there is no other choice. For more information on the Preupgrade Assistant, see Chapter 28, Upgrading Your Current System.
WarningNever perform an in-place upgrade on a production system without first testing it on a cloned backup copy of the system.