Understanding coexistence considerations for 3592 Model J1A

Coexistence support for the base 3592 support and MEDIA5 had been provided at OS/390 V2R10 and above by installing the needed full-support PTFs without the Device Services enabling PTF. The Device Services coexistence support prevented the 3590 Model J devices from coming online on a system that did not have all of the full-support PTFs installed. Installation of the base support enabling PTF then brought in all of the needed full-support PTFs and enabled the base 3592 support on that system.

In support of the new 3592 media types, MEDIA6, MEDIA7, and MEDIA8, coexistence support is also provided at OS/390 V2R10 and above. However, since full support for the new media types is only available at z/OS V1R3 and above, coexistence support is provided at OS/390 V2R10 through the installation of separate coexistence specific PTFs. At the full support release levels, coexistence support is provided by installing the needed full-support PTFs without the Device Services enabling PTF. As with the base 3592 support, installation of the new support's enabling PTF will bring in all of the needed support PTFs for MEDIA6, MEDIA7, and MEDIA8. Also, if the system is enabled for the base 3592 support and is not enabled for the new media support, it can still be used for MEDIA5 processing. Before using the new media types, ensure that all of the support code is installed as appropriate (full or coexistence). See Table 1 for a discussion of the coexistence PTFs that may be needed.

You must install coexistence PTFs on systems that will not have all of the 3592 Model J support installed (either the 3592 base support and/or the additional support for the new media types).

Review the coexistence migration tasks described in these topics.

Table 1. Coexistence migration tasks
Environment	Coexistence considerations
Stand-Alone	As described in Introduction for 3592 Model J, z/OS DFSMS and related licensed programs provide full support for the base 3592 and MEDIA5 with OS/390 V2R10 and above, with support for the new media types, MEDIA6, MEDIA7, and MEDIA8, being provided with z/OS V1R3 and above. The base 3592 support enables the tape drives to operate in the stand-alone environment in either 3590 Model B1x or 3490E emulation and to coexist with other 3590-1 or 3490 tape drives. However, to use the new media types, MEDIA6, MEDIA7, or MEDIA8, only 3590 Model B1x emulation is supported.
IBM Tape Library	As described in Introduction for 3592 Model J, z/OS DFSMS and related licensed programs provide full support for the base 3592 and MEDIA5 with OS/390 V2R10 and above, with support for the new media types, MEDIA6, MEDIA7, and MEDIA8, being provided with z/OS V1R3 and above. The system-managed tape library support allows the tape drives to operate in an ATL or MTL environment as 3590 Model B1x devices, providing device allocation and tape media management support. This support allows the 3592 Model J tape drives to coexist with other 3590-1 tape drives in the same tape library. However, prior to using the new media types (MEDIA6, MEDIA7, and MEDIA8), ensure that all existing 3592 library drives have had their microcode upgraded in support of the new media types, otherwise job failures may occur with a 3592 drive with the wrong microcode level being allocated.
OAMplex	For OAM's object support customers, in addition to the planning steps required for migration to the software support for the 3592 Model J tape drives in the stand-alone and IBM tape library environments, there are coexistence considerations your installation must take into account before you install the software in an OAMplex: For the base 3592 support and MEDIA5, OAM object tape coexistence support is provided at OS/390 V2R10 and above, through installation of the full support PTF. Coexistence support for the new media types (MEDIA6, MEDIA7, and MEDIA8) is provided at OS/390 V2R10 and above, with a separate coexistence PTF being provided at OS/390 V2R10. With z/OS V1R3 and above, OAM object tape coexistence support is provided in the full support PTF. Along with the support for the new media types (MEDIA6, MEDIA7, and MEDIA8) built into the coexistence and full support PTF is full support for the new OAM object tape data set name format (with the storage group name appended). In support of the new data set name format, coexistence and full support systems must have the DSNFMT column added to the TAPEVOL table in the Optical Configuration Database. Only one system in an OAMplex needs to run CBRSMPDS to add the TAPEVOL column, but all systems in the OAMplex need to run CBRPBIND. OAM coexistence support prevents lower-level systems from selecting volumes with ERDS Physical Identifier (EPI) values for object write requests, and it also prevents the up-level volumes (MEDIA6, MEDIA7, and MEDIA8) from being selected on a system that is not enabled for the new media support. OAM object support has coexistence considerations when running in an OAMplex environment with at least one system with the full support installed and enabled and at least one system at a release level where the new devices are supported; however, all of the support is not installed and enabled. In this mixed support environment, it is possible for a retrieve request to be received for an object, which resides on a tape cartridge volume which was written in EFMT1 track format (written on a 3592 Model J device) by a system that does not support the new devices and MEDIA5, or by a system that supports the new devices, but does not support the new media types (MEDIA6, MEDIA7, or MEDIA8), or both. If this is the case, coexistence support will be provided to allow OAM to attempt to locate an instance of OAM in the OAMplex where the full support is installed and enabled. If an instance of OAM is found where the request can be processed, the OAM on the system where the request originated will ship the retrieve request to the target system using XCF messaging services. Once 3592 Model J devices are used in an OAMplex environment and objects are written to tape volumes with the new EPI value recorded, it is expected that any OAM on a system where the full support is installed and enabled is eligible for processing requests using that volume. Therefore, the devices must be made available to all instances of OAM where the full support is installed.
OCE (Open / Close / End-of-Volume)	In support of the new media types (MEDIA6, MEDIA7, and MEDIA8), coexistence support is provided for the new media types on OS/390 V2R10 and above to prevent the new media types from being used on non-supporting systems. With the coexistence support installed, an abend will occur if an up-level volume is mounted on a down-level system.
HSMplex	For the base 3592 support and MEDIA5, HSM coexistence support is provided at OS/390 V2R10 and above, through installation of the full support HSM PTF. HSM coexistence support for the new media types (MEDIA6, MEDIA7, and MEDIA8) is provided at the OS/390 V2R10 level through the OCE coexistence PTF. At the z/OS V1R3 level and above, HSM coexistence is provided by applying both the OCE and the HSM full support PTFs. This will ensure HSM does not use MEDIA6, MEDIA7, or MEDIA8 tapes on a non-supporting system.