Restrictions for a z14 server

Restrictions that are associated with the IBM z14™ server are described as follows:

  1. Functional limitations. Not all z14 functions are available in every z/OS® release. See Table 1 and Table 2 for a list of the z14 functions available in each z/OS release. Some functions have migration or exploitation considerations (see Actions you can take before you order an IBM z14 server and Actions you can take after installing an IBM z14 server.) Many functions are enabled or disabled, based on the presence or absence of the required hardware and software. If you plan to exploit new z14 functions, you can install the software and hardware in either order; that is, there is no requirement to install either software or hardware first to exploit a specific function. However, because of outage windows and testing considerations, you might want to consider installing all the software and PTFs required for the machine and the functions you plan to exploit first, then upgrade the hardware and, finally, update your customization to exploit the new functions.
  2. z14 servers in a sysplex.
    • A Parallel Sysplex® that contains a z14 server either for a z/OS image or a coupling facility (CF) image can only contain other z14 servers, or z13®, z13s, zEC12, or zBC12 servers.

      Note that no coupling link connectivity is possible between IBM zEC12 and IBM zBC12 systems and the IBM z14 Model ZR1. Other systems, such as the z13, z13s, and z14, can connect to the z14 Model ZR1 by using the Integrated Coupling Adapter Short Reach (ICA SR) and the Coupling Express Long Reach (CE LR) coupling links. The zEC12 and zBC12 systems do not support ICA SR or CE LR, and therefore cannot have coupling link connectivity to the z14 Model ZR1. Also, the InfiniBand coupling links are not supported on the z14 Model ZR1.

      If you are running z/OS on any servers earlier than a zEC12 or zBC12 server, you cannot add a z14 server to that sysplex; that is, you will not be able to perform rolling IPLs to introduce a z14 server if you have any of the earlier servers as z/OS images or coupling facility images in the sysplex.

      The earlier servers in the sysplex must be upgraded to zEC12, zBC12, or later to have z14 servers supported in the sysplex. If you have any z/OS images or coupling facility images on an earlier server, and you intend to introduce a z14 server into that sysplex, you must migrate those images to a zEC12, zBC12, or later server before introducing the z14 server.

      GRS supports the use of FICON® CTCs for Ring configurations. However, if you are currently using ESCON CTCs for GRS ring configurations within a sysplex, consider converting to GRS Star if possible, or using XCF signaling in a GRS ring configuration. XCF sysplex signaling is preferred instead of GRS CTC connections.

    • Starting with z13, servers that require time synchronization (for example, to support a base or Parallel Sysplex) must be configured in Server Time Protocol (STP) mode. STP is designed to allow multiple servers and coupling facilities to maintain time synchronization with each other, in a coordinated timing network (CTN). STP is a hardware feature of the z14, z13, z13s, zEC12, and zBC12. The most recent servers (z14, z13, and z13s) can participate only in an STP-only CTN.

      Starting with the z14 and the IBM® Hardware Management Console (HMC) Version 2.14.0, you can use the Manage System Time task to configure an STP-only CTN. This task provides a simplified workflow for system time management, and features a visual topology display that surfaces configuration errors, if any, in the CTN.

  3. HCD and HCM support for the z14. As with previous servers, hardware can be defined on any supported OS version and server. However, dynamic activation of new server and new adapter types can be done only on z14 and future high-end IBM Z® servers.

    Dynamic activation is fully supported on z/OS V2R1 and later releases. Dynamic activation is restricted on z/OS V1R13; no hardware activation is permitted, if PCIe functions or the PNETID attribute for channel paths are defined. Limited software activation is available with hardware validation support.

    To run z/OS V1R13 on a z14 server, you require IBM Software Support Services for extended z/OS V1R13 support.

  4. Environmental Record Editing and Printing (EREP) support for the z14. Starting with the PTF for APAR IO24874, EREP supports any specification for the CPU parameter. That is, EREP does not fail an unrecognized value on the CPU parameter. If no matching records are found, EREP issues warning message IFC120I, as done in previous releases.
  5. Removal of support for running an operating system in ESA/390 architecture mode. Starting with the z14, the IBM Z® servers no longer support running in ESA/390 mode. The z14 and future systems support operating systems running in z/Architecture® mode. However, all 24-bit and 31-bit problem-state application programs that were originally written to run on the ESA/390 architecture are not affected by this change.
  6. Plan for discontinued functions. For a list of functions on the z14 that are planned to be discontinued on future servers, see Accommodate functions for the z14 to be discontinued on future servers.
  7. Unsupported hardware features. The following hardware features are not supported on the z14. They cannot be ordered on the z14 and cannot be carried forward from an upgrade on an earlier server to the z14.
    • Host Channel Adapter fanout:
      • The HCA2-O and HCA2-O LR features are not supported on any of the z14 models.
      • The HCA3-O and HCA3-O LR coupling fanouts are not supported on the z14 Model ZR1. This model requires ICA-SR and CE-LR fanouts.
    • IFB-MP Daughter Card #0326
    • STI-A8 Mother Card #0327
    • InterSystem Channel-3 (ISC-3) coupling links feature
    • CHPID type OSN (OSA-Express® for NCP) is not supported on the OSA-Express5S GbE LX feature
    • OSA-Express4S features
    • Crypto Express4S feature
    • FICON Express8 features
    • Flash Express, which is replaced by Virtual Flash Memory on the z14
    • IBM zAware Firmware Appliance. IBM zAware analytics functions are now available through software, starting with IBM Operations Analytics for z Systems® Version 3.1. For more information, go to IBM Operations Analytics for z Systems.
    • STP Mixed CTN. The zEC12 and zBC12 were the last IBM Z® servers to support connections to an STP Mixed CTN. This also includes the Sysplex Timer (9037). Starting with the z13, servers that require Time synchronization, such as to support a base or Parallel Sysplex, require Server Time Protocol (STP) and all servers in that network must be configured in STP-only mode.
    • IBM zEnterprise® Application Assist Processor (zAAP). IBM continues to support running zAAP workloads on IBM z Integrated Information Processors (zIIPs). IBM has removed the restriction preventing zAAP-eligible workloads from running on zIIPs when a zAAP is installed on the CEC. This change was intended to help facilitate migration and testing of zAAP workloads on zIIPs. With a z14, one CP must be installed with the installation of any zIIPs or prior to the installation of any zIIPs. The total number of zIIPs purchased cannot exceed twice the number of CPs purchased. However, for upgrades from zEC12s with zAAPs, conversions from zAAPs can increase this ratio to 4:1.
  8. Carry forward hardware features. The following hardware features are not orderable on z14 servers. If they are installed on your existing server at the time of an upgrade to a z14 server, they can be retained or carried forward.
    • HMC #0092, #0094, #0095, and #0096
    • TKE with/4767 #0096 or #0097
    • OSA-Express4S 1000BASE-T #0408
    • OSA-Express5S GbE LX #0413
    • OSA-Express5S GbE SX #0414
    • OSA-Express5S 10 GbE LR #0415
    • OSA-Express5S 10 GbE SR #0416
    • OSA-Express5S 1000BASE-T #0417
    • FICON Express8S 10KM LX #0409
    • FICON Express8S SX #0410
    • FICON Express16S LX #0418
    • FICON Express16S SX #0419
    • 10GbE RoCE Express #0411
    • TKE workstation #0842
    • TKE workstation w/4767 #0847
    • Addl smart cards #0884
    • TKE Smart Card Reader #0885 or #0891
    • Crypto Express5S #0890
    • Fill and Drain Kit #3378
    • Universal Lift Tool/Ladder #3759.

    For information about supported storage controllers, see Ensure that you are using supported servers and storage controllers.