z/OS Version 2 Release 3 Hardware Configuration Definition Planning IBM GA32-0907-30 Note Before using this information and the product it supports, read the information in “Notices” on page 129. This edition applies to Version 2 Release 3 of z/OS (5650-ZOS) and to all subsequent releases and modifications until otherwise indicated in new editions. Last updated: 2019-02-16 © Copyright International Business Machines Corporation 1989, 2018. US Government Users Restricted Rights – Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp. Contents List of Figures...................................................................................................... vii List of Tables........................................................................................................ ix About this document.............................................................................................xi Who should use this document...................................................................................................................xi How to use this document.......................................................................................................................... xi z/OS information..........................................................................................................................................xi How to send your comments to IBM.....................................................................xiii If you have a technical problem................................................................................................................xiii Summary of changes...........................................................................................xiv Summary of changes for z/OS Version 2 Release 3 (V2R3)..................................................................... xiv Summary of changes for z/OS Version 2 Release 2 (V2R2) as updated September 2016..................... xiv Summary of changes for z/OS Version 2 Release 2 (V2R2)...................................................................... xv z/OS Version 2 Release 1 summary of changes....................................................................................... xvi Chapter 1. Introduction......................................................................................... 1 What an I/O configuration is........................................................................................................................ 1 I/O configuration definition process............................................................................................................1 Defining an I/O configuration to the software....................................................................................... 2 Defining an I/O configuration to the hardware...................................................................................... 4 Ensuring that the software and hardware definitions match................................................................ 5 Changing hardware and software I/O configuration definitions.................................................................7 Making software-only dynamic changes............................................................................................... 7 Making both hardware and software dynamic changes........................................................................ 8 Making a hardware only dynamic change on a Standalone Coupling Facility.......................................9 Using HCD I/O Autoconfiguration for automatic discovery of FICON connected DASD and tape control units and devices........................................................................................................................9 Using HCM for I/O definition........................................................................................................................9 Using CHPID Mapping Tool for assigning physical hardware attributes to CHPIDs................................ 10 Chapter 2. Planning your I/O configuration definition........................................... 11 Components of an I/O configuration.........................................................................................................11 Logical channel subsystems................................................................................................................ 12 Logical partitions.................................................................................................................................. 12 Logical control units for I/O devices.................................................................................................... 12 Channel path numbering......................................................................................................................13 Selection of the path to access an I/O device..................................................................................... 13 Making decisions about your configuration.............................................................................................. 13 IBM zSeries and IBM Z platform considerations.................................................................................14 Defining operating system data........................................................................................................... 14 Defining switch data.............................................................................................................................15 Defining processor, PCIe-based functions,logical channel subsystem, partitions, channel path data, and subchannel sets.............................................................................................................. 15 Defining multiple subchannel sets...................................................................................................... 18 Defining control unit data.....................................................................................................................18 Defining I/O device data.......................................................................................................................19 Deciding about JES3 initialization stream checker data.....................................................................20 Understanding a sysplex configuration.....................................................................................................20 Defining coupling facility components in a sysplex.............................................................................20 Managing IOCDSs and IPL attributes across a sysplex.......................................................................24 iii Using automatic tape switching...........................................................................................................25 Defining shared channel paths..................................................................................................................26 Considerations for sharing channel paths........................................................................................... 26 Defining logical partition access to a channel path.............................................................................27 Processors communicating through shared ESCON or FICON channel paths................................... 28 Defining dynamically managed channel paths....................................................................................30 Defining spanned channel paths............................................................................................................... 31 Considerations for spanning channel paths........................................................................................ 32 Creating over-defined channel paths........................................................................................................32 FICON channels......................................................................................................................................... 32 Channel path definitions...................................................................................................................... 32 Dynamic activation............................................................................................................................... 33 Migrating to FICON channels............................................................................................................... 33 Defining special devices and special secondary devices......................................................................... 35 Defining a special device (3390S)....................................................................................................... 36 Defining a special secondary device (3390D)..................................................................................... 36 Defining a special FBA device (FBA)......................................................................................................... 36 Defining IQD CHPIDs and device types.....................................................................................................37 Defining PCIe based functions (RoCE and zEDC)......................................................................................38 Specifying an I/O device number.............................................................................................................. 38 Replicating I/O device numbers...........................................................................................................39