IBM Migration, installation and customization Enhancements, ZSeries Bimodal Support for z/OS

This consistent coexistence, migration and fallback policy applies to release migrations for:

•Single system confi gurations

•Individual systems within a multisystem confi guration

•Cases where a simultaneous IPL is used to migrate all systems in a multisystem confi guration at the same time.

For additional information on coexistence and release migration information, refer to z/OS Planning for Installation (GA22-7504) at: ibm.com/servers/eserver/zseries/zos/ bkserv/fi nd_books.html.

The following table describes the migration/coexistence supported releases. The release shown in column 1 is the highest release running in a multisystem confi guration.

Migration/Coexistence Supported Releases (OS/390 & z/OS)

Release Migration/Coexistence Release

z/OS R4 z/OS R4, z/OS R3, z/OS R2, {z/OS R1, OS/390 R10}

z/OS R5 z/OS R5, z/OS R4, z/OS R3, z/OS R2

z/OS R6 z/OS R6, z/OS R5, z/OS R4, z/OS R3

z/OS R72 z/OS R7, z/OS R6, z/OS R5, z/OS R4

1.OS/390 R10 and z/OS R1 treated as one coexistence level

2.z/OS R7 is planned to be available September 2005

This information is being provided to you to facilitate release planning and to help ensure appropriate position- ing for future software migrations.

Note: Specifi c functions might only be available on the up-level systems, or it might be necessary to up-level all systems to enable some functions.

For additional information on z/OS planning, refer to z/OS and z/OS.e Planning for Installation, available on the z/OS Web site in the z/OS Library at: ibm.com/servers/eserver/ zseries/zos.

For the latest information regarding z/OS and OS/390 marketing and service withdrawal dates visit: ibm.com/ servers/eserver/zseries/zos/support/zos_eos_dates.html.

Migration, installation and customization

enhancements

For information on migration to the latest z/OS releases, see the z/OS Migration Web page ibm.com/zseries/zos/ migration. The publications are available from this site for helping to plan the migration to z/OS 1.6.

zSeries Bimodal Support for z/OS

IBM provides is announcing the z/OS Bimodal Migration Accommodation Offering to assist customers in migrat- ing from OS/390 to z/OS. This addresses many customer requests to have a “fallback” option to 31-bit mode when

first migrating to z/OS in 64-bit mode on a z/Architecture server. IBM has reconsidered the investment in 31-bit sup- port on a zSeries server to encourage our customers to move forward. This offering is available for 6 months for each z/OS license (5694-A01) starting from the registration of a z/OS license to a z/Architecture server. This offering applies to z/OS Version 1 Release 2, 3, and 4, and will not be provided for z/OS 1.5 or for any z/OS.e releases.

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