zOS pp

  1. Other Names:
    IBM latest mainframe:
    • Other Names:
    • –“Big Iron”
    • –“Enterprise Server”
    • –“Main Server” or just “Server”
    • –IBM System Z
    •      “Z” stands for Zero Down Time
    • IBM latest mainframe:  
    •    IBM® z13
  2. Types of businesses using mainframes
    • Banking
    • Finance
    • Health care
    • Insurance
    • Public utilities
    • Government
    • and a multitude of other public and private enterprises
    • the mainframe computer continues to form the foundation of modern business
  3. 1950’s
    • 1950’s: Mainframe development started
    • First Generation- IBM 705 followed by IBM 1401
    • 1960’s: S/360 style
    •         Third generation mainframe
    •          Commercial or Scientific
    • 1970’s: S/370 style
    •        Next Generation
  4. 1980’s
    • 1980’s–4341, 4381, 3033 etc
    • 1990’s–S/390 style
    • 2000’s–z/9 z/10 z/13 series
  5. The term mainframe in this text means computers that can:
    • Supports thousands of applications
    • Host many users
    • Input/output devices to simultaneously serve thousands of users
  6. A mainframe:
    • Central data repository
    • Primary hub
    • Found in a corporation's data processing center
    • Houses commercial databases, transaction server, and applications
    • Linked to users through less powerful devices such as workstations or terminals
  7. Implies a centralized form of
    • Computing (supports Cloud computing)
    • Backup/recovery
    • Security
    • Stable
    • Virtualization
    • Clustering

    • Saves customers from having to manage updates to more than one copy of their business data
    • Increases the likelihood that the data is current
  8. Two categories of workload:
    • Batch processing
    • Online Transaction processing
  9. MTBF
    • MTBF 99.999% (Mean Time Between Failure)
    • Reduces SPOF (Single Point of Failure)
    • Provides for CoD (Capacity on Demand)
    • Reduces TCO (Total Cost of Ownership)
  10. Mainframe History
    • 1960s, the course of computing history changed dramatically
    • mainframe manufacturers began to standardize the hardware and software they offered to customers.
    • The introduction of the IBM System/360™ (or S/360™) in 1964 –Signaled the start of the third generation
    • –The first general purpose computers

    • Could perform both types of computing
    • –Commercial
    • –Scientific
    • –Use microcode (firmware) for machine instructions
    • Older mainframes required:
    • Large amounts of space
    • High power consumption
    • High air-conditioning requirements
    • Occupied 2,000 to 10,000 square feet of space
  11. Mainframes and first programming languages
    Support for other languages
    • Mainframes and first programming languages:
    • Assembler
    • COBOL
    • PL/1
    • Support for other languages:
    • Java
    • C++
    • Perl
    • ReXX
  12. CICS
    • CICS (Customer Information Control System)
    • Transaction Processing System (C.I.C.S.)
  13. Problems with older O/S
    • Jobs had to wait for information to be
    • read in from,
    • or written out to, a device such as a tape drive or printer.
    • Input and output (I/O) take a long time compared to the electronic speed of the processor.
    • jobs waited for I/O, the processor was idle (wasted time)
    • No multiprocessor or multitasking

    • The operating system
    • processed each request or job as a unit
    • did not start the next job until the one being processed had completed.
    • This arrangement worked well when a job could execute continuously from start to completion
  14. z/OS Multiprocessing / Multitasking
    • Controlled by O/S:
    • Support for up to 64 engines in a single logical partition
    • Up to 1.0 terabyte (TB) of real memory per logical partition
    • Software designed to relieve requirements of O/S:
    • JES2(3)  Job Entry Subsystem
    • RACF  Resource Access Control Facility (Security)

    –Spooling  Queues for input and output jobs
  15. PF key assignments: Function Key
    • Enter Ctrl (right side)
    • Exit, end, or return PF3
    • Help PF1
    • PA1 or Attention Alt-Ins or Esc
    • PA2 Alt-Home Cursor movement Tab or Enter
    • Clear Pause
    • Page up PF7
    • Page down PF8
    • Scroll left PF10
    • Scroll right PF11
    • Reset locked keyboard Ctrl (left side)
  16. TSO
    • TSO: Time Sharing Option
    • TSO divides available CPU time and allocates the slices to users.
    • time slices are very short
    • The system cycles through the requesting users very quick
    • It appears as if they have simultaneous access

    • An on-line terminal-oriented system
    • –Gives access to IBM Mainframe MVS, OS/390, ZOS files and programs, job submission and the print spool
    • –Generally used for creating and editing files and programs and for testing
    • A multi-user environment
    • –for the IBM MVS mainframe operating system.
    • –New name z/OS Operating System
  17. l tso
    Launch TSO: l tso
  18. ISPF
    • Interactive System Productivity Facility
    • a menu driven full screen interface
    • interfaces to the most commonly accessed TSO features.
    • includes facilities to:
    • –Create / edit source code for programming
    • –Create and Edit data files
    • –Browse member, browse files
    • –Manage data and programs
    • Submit jobs for processing (COBOL Compiles)
    • Retrieve the results
    • Delete unwanted results
  19. ISPF
    • Has a editor
    • The ISPF editor facility allows you to edit
    • –source code, JCL, and Data
    • Editing functions
    • –Insert lines
    • –Repeat lines
    • –Copying lines
    • –Moving lines
    • –and deleting lines
    • You may customize the environment through edit modes and the creation of edit profiles.
    • Advanced techniques like
    • –finding and changing text
    • –excluding and redisplaying lines
    • -as well as shifting text will be covered
  20. ISPF utilities include
    • –library utilities,
    • –data set utilities,
    • –move/copy utility,
    • –data set list utility,
    • –and compare/search utilities.
    • –submit a job for background processing,
    • –monitor the status of a job while it is waiting, executing, or waiting for its output to print,
    • –and how to retrieve the output for a job that is completed
  21. SDSF provides
    • System Display and Search Facility)
    • –monitor, manage, and control your z/OS MVS/JES2 system JES
    • –Job Entry Subsystem
    • SDSF panels provide current information about
    • –Jobs and output
    • –devices (including printers, punches, initiators, lines, spool offloaders and spool volumes)
    • –and system resources
    • With SDSF panels, there is no need to learn or remember complex command syntax.
    • SDSF's
    • –action characters
    • –overtypeable fields
    • –action bar, pull-downsand pop-up windows allow you to select available functions
  22. JES
    • Job Entry Subsystem
    • JES is a systems management tool
    • provides you with information to monitor, manage, and control your z/OS
    • you can:
    • –Control job processing (hold, release, cancel, and purge jobs).
    • –Monitor jobs while they are running.
    • –Browse jobs without printing.
    • JES-managed initiators (JES2), job classes, and job class groups (JES3).
    • Control printers, punches, functional subsystems (JES3), and NJE resources.
    • Control your JES spool configuration
    • consists of panels that provide immediate and current information about
    • –jobs, –printers, –queues, –and resources in z/OS
    • You use series of panels
    • –you can enter (E)JES commands to control the processing of jobs and the operation of system resources
    • You can also issue system commands from the (E)JES panels.
    • With (E)JES you can easily access and modify
    • –all attributes for jobs,
    • –started tasks,
    • –TSO users,
    • –APPC/MVS transaction jobs,
    • –or processes running under Unix System Services residing anywhere
  23. JCL
    • Job Control Language
    • The language used by the z/OS, MVS mainframe
    • –Used to compile your source code
    • –Used to execute (run) jobs to
    • –Not user friendly
    • Used to execute the various jobs required by the user
  24. PDF
    • Program Development Facility
    • provides the application developer with services necessary to create and test applications  
    • Different activities for the user include:
    • generate tables
    • manage data sets
    • create test messages
    • trace and debug applications
    • The center of the PDF is the ISPF Primary Option Menu
    • The menu contains a list of options which may be customized
    • The main menu on one z/OS system might not match the one on another system.
  25. Standard options for the PDF Main Menu are
    • Settings
    • View
    • Edit
    • Utilities
    • Foreground
    • Batch
    • Command
    • Dialog Test
    • IBM Products
    • SCLM
    • Workplace

    Note: These options may vary between systems
  26. ISPF
    • Settings:     Used to display and change ISPF parameters
    • You can change key definitions and display styles
    • View:           Allows you to view data sets
    • Edit:            Allows you to create or update data sets
  27. ISPF
    • Utilities:       Utility system and data set management functions,             such as printing, renaming, or deleting data sets
    • Foreground:     Used to interactively run language processing                 programs such as COBOL.
    • Batch:           Generates and submits batch jobs through job control statements
    • Command:     Enter TSO commands while ISPF remains active
  28. You can navigate through ISPF in four different methods.
    • Action Bars
    • Point-and-Shoot
    • Selection by Option Code
    • Function Keys
  29. Option vs Command:
    • The command area for menu screens is identified by:
    • Option ===>
    • For other screens, ISPF identifies the command area by:
    • Command ===>
    • You can get to the command area quickly by pressing the Home key
    • No matter where the cursor may be, the home key will immediately place the cursor in the command area
  30. Modal pop-up windows:
    Modeless pop-up windows:
    • Modal pop-up windows:
    • require user interaction or some kind of reply before the underlying dialog continues.

    • Modeless pop-up windows:
    • allow you to continue to interact with the underlying dialog before you choose to interact with the pop-up
  31. Key Functions:
    • PA1 Attention:         Interrupt the current position.
    • PA2 Reshow:         Redisplay the current screen.
    • PF1/13 Help:         Enter the tutorial, or view help.
    • PF2/14 Split:         Enter split screen mode.
    • PF3/15 End:         Terminate the current operation.
    • PA4/16 Return:         Return to the primary option menu.
    • PA7/19 Up:         Move the screen window up.
    • PF8/20 Down:         Move the screen window down.
    • PF9/21 Swap:         Activate the other logical screen in split screen mode.
    • PF10/22 Left:         Move the screen window left.
    • PF11/23 Right:         Move the screen window right.
    • PF12/24 Retrieve:     Redisplay the last issued ISPF command.
  32. Split screen:
    • To enter split-screen mode
    • You place the cursor on the line where you want the split to occur
    • Then press PF2
    • Immediately the screen splits into two logical screens, and each logical screen is an independent session
    • To switch between screens press PF9.
    • To end split screen mode
    • Simply end one of the sessions by typing ‘exit’ on the command line
    • Or pressing F3 from the Primary Options Menu.
  33. Data Sets in z/OS
    • In the z/OS environment, files are known as data sets
    • z/OS lets you maintain two types of data sets under TSO:
    • Sequential
    • Partitioned
  34. Datasets History
    • Punched Cards
    • 80 columns in size
    • Used in an MVS system in the 1960s existed as 80-column punched cards
    • Today's JCL and program source code on a modern z/OS system is maintained as a file of 80-byte records.
    • Every statement is a full 80 bytes long even if it is completely blank.
  35. Sequential Datasets
    • Records of a file can be retrieved only in the same order they were written
    • To process a record somewhere within the file, you have to read all of the preceding records
  36. Partitioned Dataset
    • A partitioned data set (PDS) consists of
    • A directory and
    • One or more members
    • A PDS is also called a library  
    • There are no subdirectories
    • file naming and the use of partitioned data sets support all the processing that occurs on a mainframe under z/OS
    • Each member is functionally the same as a sequential data set:
    • you can process an individual member of a partitioned data set as if it were a sequential data set
    • you can process the entire library, the entire PDS, as a single file
  37. Data Sets General Information:
    • The minimum allocation for a data set is one track of disk space   
    • For a small file that contains only a small amount of information, much space can be wasted if it is stored in a data set all by itself.
    • Instead it can be stored as one of many members in a partitioned data set
    • Each partitioned data set contains a directory and data area.
    • The directory maintains housekeeping information about the members stored in the data area.
    • It stores an index of member names and their locations.
  38. Partitioned Dataset naming convention:
    • Standard TSO data set naming calls for three qualifiers within the name of the data set
    • Qualifiers can be up to eight characters long and when you specify a data set name, you separate the qualifiers by periods.
    • The data set name consists of three qualifiers listed below.
    •  High-level Qualifier
    •  User Determined Qualifier
    •  Type of Data
    • Example:    COMP1081.FALL2013.DATA
    •             KC02132.LAB01.COBOL
  39. Partitioned data sets and members:
    • Appear to the z/OS operating system to be no different than any other type of data set
    • By seeing the name it is not possible to tell absolutely if the data set is partitioned or not
    • The operating system has the information internally about its organization, but this is not necessarily reflected in the name
    • In order to deal with a specific member of a partitioned data set, the member name is placed at the end of the data set name inside parentheses
    • The member name, which is the name in parentheses, can be up to eight characters long, and must start with a letter
  40. The management of the PDS:
    • Its creation and internal organization, is handled by the z/OS operating system
    • When a member of a PDS is retrieved or browsed, only the name is required
    • The z/OS operating system handles its extraction from the data set structure
    • Many times programmers maintain two PDSs for a project
    • One is for source code, and it will carry a name as the third qualifier like COBOL, FORT, PLI, or ASM
    • Additionally, there will be a PDS for JCL statements. These carry a name of "CNTL" as the third qualifier
    • The standard names cause ISPF to default to convenient screen presentation formats for each language
  41. ISPF and Datasets: View Entry Panel
    • The View Entry Panel appears when you select View (option 1) from the ISPF Primary Option Menu.
    • This option facilitates viewing and browsing of a data set, but does not provide the ability to edit or change data
    • Two areas of particular interest here are the fields in the panel and the action bar at the top of the panel.
  42. ISPF Library section
    • Permits you to enter a data set name
    • The project ID identifies the project associated with the data set.
    • It usually defaults to the user ID from your LOGON command
    • The three components of the data set name
    • Project
    • Group
    • and Type, are strung together to form the z/OS data set name.
    • Another example:
  43. Specify a Member Name
    • If the data set is partitioned, you can specify the name of the member in the Member field
    • You may also enter a pattern for the member name
    • A pattern consists of a partial member name plus the symbols * or % or both (wildcards)
    • For example:
    • the member name PAY* will select all members that begin with the three letters P-A-Y
    • If the data set you specify is partitioned, and you specify a pattern of the member name, or if you do not specify a member name at all, you will receive a member list
  44. PDS Members:
    • After you have selected the member you want to display, the browse panel displays the first 22 lines of the data
    • F8 moves forward through the file
    • F7 moves you backup (upwards) through the file
    • The heading line displays the data set name, current line position, and current columns displayed
    • In the following screen, only browsing is allowed
    • You are not permitted to edit the member
  45. View member data:
    • Scrolling functions let you specify both the direction and amount you move as you peruse the data
    • PF7 and PF8 move the window up and down respectively
    • PF10 and PF11 move it left and right
    • You may specify the amount of the scroll by entering a value in the SCROLL field at the lower right hand side
    • The default value is HALF
    • This means that when you press any of the function keys mentioned above, the window moves a half page in the direction desired
  46. You can use the FIND command to:
    • Search a member for a specific string of characters
    • You type FIND at the command line followed by the string
    • If the search string contains blanks or characters, enclose it in either single or double quotes.
    • An example is:
    • Use “ “ to include spaces
    • This command will find the next line that contains the target string
    • You can also add one of the following qualifiers after the search string
Card Set
zOS pp
zOS pp