Performing a Fast Service Upgrade

The traditional use for the Fast Service Upgrade (FSU) process is to upgrade your z/VSE system to the current maintenance level. This means that you perform an FSU to install a new modification level of z/VSE – referred to as performing a service refresh.

If you are currently a z/VSE 6.1 user and you want to install z/VSE 6.2, you can use the FSU process for installation as well. Installing a new version/release of z/VSE through FSU is generally referred to as performing a release upgrade. Make sure that you have read Installing z/VSE 6.2. It describes planning tasks and prerequisites required for performing a release upgrade through FSU.

The FSU consists of a dialog sequence that you follow. Please proceed as described in the following table, depending on whether you want to perform a release upgrade or do a service refresh.

Table 1. Version/Release Upgrade or Service Refresh
Version or Release Upgrade	Service Refresh
Do not perform a downlevel check	Perform a downlevel check Your current system status is checked and compared with the refresh level. This step does not change your system.
Perform the FSU preparation A job stream is created which restores the latest level of the FSU function from tape. In this case, it is the FSU function from the new z/VSE 6.2 system. Note that the job stream must run before you proceed.	Perform the FSU preparation A job stream is created which restores the latest level of the FSU function from tape.
Perform the FSU installation Your system is replaced by the new z/VSE version. The installation of a release upgrade is mainly the same as the one for a service refresh. FSU installation consists of two stages. See What You Must Know Before You Start with the Fast Service Upgrade and FSU Processing and Space Requirements for more information.	Perform the FSU installation Your system is replaced by the new service refresh. FSU installation consists of two stages. See What You Must Know Before You Start with the Fast Service Upgrade and FSU Processing and Space Requirements for more information.