For z/OS 2.5, which we recently announced, there have been a number of statements of direction around changes in functional content of z/OS. I will focus on the removals that planned in this blog.

First and by far the most significant is the removal of JES3 (Job Entry Subsystem 3). z/OS has had two JES implementations that grew up from customers. JES2 or HASP and JES3 or ASP. For years JES2 has dominated the customer base both in number of sites, operating system images, and even size of image. The largest customers run JES2 these days. Years ago, before parallel Sysplex it was common for large customers to run JES3. Without any encouragement by IBM the customers have largely moved to JES2. The features being added to the JES components have therefore been focused on JES2. As a result IBM announced in 2017 that JES3 would be removed from z/OS in the future. In 2019 this was reiterated in another announcement. The z/OS 2.5 preview reiterated this again and indicated that 2.5 would be the last release to include JES3.

JES3 customers have the option of migrating to JES2 which is included in z/OS, or another option is to use JES3Plus. Phoenix software is offering a JES3plus. The JES3Plus option intends to run a JES3 derivative product on z/OS which would maintain all the existing exits, JCL/JECL, Operator commands and operational procedures. JES2 migration does require customers to change all those items as part of the migration. The migration to JES2 can be time consuming but there are vendors out there who can do a lot of the migration for a fee.

In addition to JES3 we also announced the Bulk Data Transfer – BDT feature will be removed in a future deliverable. In fact BDT is only planned to be retained in z/OS through V2.5. BDT comes in two priced features, SNA/NJE and File to File (FTF). The BDT SNA/NJE version is only applicable to JES3 customers. JES2 customers have SNA/NJE built into JES2. BDT FTF is applicable to both JES2 and JES3 customers. But BDT is a very very old technology base, it assists customers to copy and move datasets from one system to another. An astute reader will recognize that moving datasets could be done today with FTP, with SSH, with MQ file transfer, with Sterling Direct, or any number of vendor options.

So again here BDT customers have the option of migrating their functional requirement to one of the other IBM options or they might want to look at the Phoenix offering announced for BDT similar to JES3Plus.

Beyond this we removed the need to specify maxsharepages. This setting was put in place to control the consumption of common storage which used to accompany the use of shared memory. The real storage manager no longer needs any common storage for using shared memory. So the option becomes obsolete.

We’ve also removed some HFS options (as opposed to zFS) since we have deprecated HFS. There are also some removals in the communication area. We replaced the SSL configurations of TN3270, FTP and DCAS to use AT-TLS policy. This not only unifies the the configuration but also brings the code up to the most recent level of capability.

Lastly in ISPF, the workstation agent has been removed as well as the support in ISPF for HFS.

While there are quite a few removals these should reduce the need to know about these features or capabilities as they are essentially no longer needed.