Software upgrade or replacement

Use this information to understand special considerations of the system and its software when you upgrade or replace an IBM i release.

Releases supported and system model information for IBM i upgrades
Upgrades to current releases require that you be at a certain level of software and hardware. This information shows the supported combinations for source and current target releases for software and also system model information in relation to IBM i.
Installation and IBM-supplied objects
When you replace your software with a new IBM i release, by default the system keeps changes that you made to some IBM-supplied objects.
Compressed objects and storage space
All of the licensed programs and some objects of the IBM i operating system ship in a compressed form. This requires less storage space on your system. The system decompresses objects according to certain criteria, which could affect the performance of the system.
Files that the system deletes during installation
If you have created logical files over IBM-supplied physical files in QSYS, the logical files will be deleted during the IBM i installation process.

Parent topic: Concepts for software installation