Siebel Database Upgrade Guide for DB2 for z/OS > How the Siebel Database Upgrade Works >

About the z/OS Upgrade

Historically, Siebel production environment upgrades were primarily performed on the z/OS host (mainframe-centric) but you could choose to upgrade your development environment using either a mainframe-centric or midtier-centric process. Since Siebel CRM 8.0, only mainframe-centric development environment upgrades are supported for DB2 for z/OS. In a mainframe-centric upgrade, all upgrade DDL statements (CREATE, DROP, ALTER, and GRANT) and DML (INSERT, UPDATE, DELETE, and SELECT) are executed on the mainframe host.

You initiate a Siebel database upgrade on DB2 for z/OS from a midtier platform (Windows or UNIX) using the Siebel Upgrade Wizard, which automatically generates the DDL and DML files necessary for the upgrade. The Siebel Upgrade Wizard is also run from the midtier to import seed data and the upgraded repository.

You must manually transfer the DDL and the data migration DML files generated on the midtier platform by the Upgrade Wizard to the DB2 host where they are unpacked and applied; this process is guided on the mainframe using REXX execs and ISPF panels. This manual portion of the upgrade, which runs directly on the z/OS host, allows you to tailor the upgrade process to suit your hardware environment and to minimize downtime.

Each ISPF Upgrade panel has a bookmark label and message, indicating the last step completed or currently in progress. These bookmarks guide you through the upgrade process; you cannot rerun jobs that have completed successfully or run jobs out of sequence.