z/OS Introduction and Workshop
Configuration and Customization
Unit objectives
After completing this unit, you should be able to:
• Describe IPL process
• Describe IPL device and LOADPARM device
• Describe Support Element and HMC
• Describe System Parameters/Definitions
• Determine IPL and LOAPARM device using MVS commands
• Determine LOADPARM member read at IPL time
• Determine parameter libraries read at IPL time
• Determine parameter library members read at IPL time
System Initialization
The system operator supplies parameters instructing the system to load :
The bootstrap code on the IPL volume is loaded into storage at address 0 and control
passed to it
The bootstrap the reads the IPLTEXT program IEAIPL00 which is given control and the
complex task of loading the system starts
Hardware Management Console (HMC) – Support Element (SE)
Support Element (SE)
Choice:
2 laptops inside the IBM Z frame
2 1U rack slots
Hardware Management Console (HMC)
Choice:
1 Standalone desktop networked with all SE’s
1 Rack mount device netwokred with all SE’s
Hardware Management Appliance (HMA)
2 1U racks slots running HMC and SE together
HMA IBM Z network with a primary HMA
New with z15
Hardware Management Console (HMC) – Support Element (SE)
Hardware Management Console (HMC) – Support Element (SE)
Disk Device Address of SYSRES and SYS1.IPLPARM
1000
0CE3W1
Initial Program Load (IPL)
Disk Device Address
1000 Bootstrap (cylinder 0)
IPLTEXT
immediately following bootstrap
Initial Program Load (IPL)
IPL 1000 LOADPARM 0CE3W1
Disk Device Address Disk Device Address
0CE3 1000 Bootstrap (cylinder 0)
SYSx.IPLPARM
IPLTEXT
LOADW1
immediately following bootstrap
System Definitions
IPL loadparm SYS1.IPLPARM(LOADxx)
SYS1.IPLPARM(LOADW1)
IEASYM (W1,SV,VN)
INITSQA 0000K 0512K
IODF 00 SYS1 MVS 00 Y
NUCLEUS 1
NUCLST SV N
SYSCAT VPMVSB113CMASTERV.CATALOG
SYSPARM (00,LV,SV,VN)
SYSPLEX SVSCPLEX
PARMLIB VENDOR.PARMLIB
PARMLIB SVTSC.PARMLIB PARMLIB(IEASYSxx)
PARMLIB LVL0.PARMLIB
PARMLIB SYS1.PARMLIB
IEAIPL00
IEAIPL00 prepares the system by clearing central storage to zeroes then
defines storage areas for the master scheduler
SYS1.NUCLEUS is located and a series of modules loaded which construct
the normal environment of control blocks and subsystems
The first part of the Nucleus Initialization Program is then loaded
Storage Map
E L S Q A /E S W A /2 2 9 / 2 3 0 / 2 4 9
E xte n d e d E x te n d e d U s e r R e g i o n
P r iv a t e
E x te n d e d C S A
E xte n d e d
E x te n d e d P L P A /F L P A / M L P A
C o m m o n
E x te n d e d S Q A
E x te n d e d N u c l e u s
16 M B
N u c le u s
S Q A
C o m m o n P L P A /F L P A /M L P A
C SA 1 6 M
L S Q A /S W A /2 2 9 / 2 3 0 / 2 4 9
U s e r R e g io n
P r iv a t e
20K B
S y s te m R e g i o n
4K B
C o m m o n PSA 0
Data Areas and Control Blocks
4K pages of
system information
4K page of system
information can reside
in a ‘frame’ or ‘slot’
Some 4K pages of system
information are marked as
a permanent resident in
real storage – ‘frame’ only
Systems are operational and
connected to CF (Coupling Facility)
System Definitions
z/OS is highly configurable to best serve a customers workload
System definitions (system parameters) are read during z/OS initialization
The values of many system parameters can be changed dynamically
Default values exist for the majority of system parameters
More matured systems change the defaults as their workloads change
It is important to develop a back out plan for any system definition change
System Initialization (IEE252I messages)
System Log (Trail of IEE252I messages)
IEE252I MEMBER member FOUND IN parmdsname
Explanation: This is an informational message that appears only in the hardcopy log when member member
is found in parmlib dataset parmdsname
In the message text:
member is the parmlib member name that is being processed.
parmdsname is the parmlib data set where member member is located.
System Action:
The system continues processing.
System Programmer Response:
Check the hardcopy to see if all the members in parmlib specified in LOADxx
or in operator input are being used correctly and are found in the correct parmlib data set.
Source: Master scheduler, IPL/NIP
System Definitions
D IPLINFO
SYSTEM IPLED AT 08.41.25 ON 01/29/2007
RELEASE z/OS 01.07.01 LICENSE = z/OS
USED LOADW1 IN SYS1.IPLPARM ON 0CE3
ARCHLVL = 2 MTLSHARE = N
IEASYM LIST = (W1,SV,VN)
IEASYS LIST = (00,LV,SV,VN) (OP)
IODF DEVICE 0CE3
IPL DEVICE 1000 VOLUME VIMVSB
D PARMLIB
PARMLIB DATA SETS SPECIFIED
AT IPL
ENTRY FLAGS VOLUME DATA SET
1 S VPMVSD VENDOR.PARMLIB
2 S VTMVSG SVTSC.PARMLIB
3 S VTLVL0 LVL0.PARMLIB
4 D VIMVSB SYS1.PARMLIB
SYS1.IPLPARM LOADxx member startup parameters
Display IPLINFO and system PARMLIB concatenation
Master JCL for Master Scheduler
CLIST to easily find system parm and proc members
View system PARMLIB concatenation
SYSPARM IEASYSxx values in PARMLIB
IEASYS00 is read first. IEASYS00 has few parameters
IEASYSLV is read 2nd. IEASYSLV has more parameters
IEASYSSV is read 3rd-duplicate parm values are overridden
IEASYSVN the last member read has only one parm entry
System Libraries
SYS1.LINKLIB prime system software library
– LNKLST concatenation
SYS1.LPALIB system subroutines
SYS1.NUCLEUS basic supervisor modules
SYS1.PROCLIB system procedure JCL
– PROCLIB concatenation
SYS1.PARMLIB control parameters
– PARMLIB concatenation
System search order for programs
Programs (load modules) must be in central storage and therefore in the virtual storage
of the address space before they can run
System has a defined search order for a newly requested program
Search order for programs
1) JCL STEPLIB (if present)
2) JCL JOBLIB (if present)
3) Link Pack Area (LPA)
Fixed LPA (FLPA)
Modified LPA (MLPA)
Pageable LPA (PLPA)
4) LINKLST (Concatenated Group of Partitioned Data Sets)
SYS1.LPALIB
The Link Pack Area (LPA) is built at IPL time from the modules defined
in the LPALSTxx member of parmlib.
SYS1.LPALIB is always the first library used unless overridden by a
SYSLIB statement
Modules are loaded into common storage at IPL time and so are
available to all address spaces
SYS1.LPALIB
Fixed LPA comprises those modules defined in IEAFIXxx that are fixed in central storage
Pageable LPA comprises most other modules whose pages are eligible to be stolen
Modified LPA has modules which are temporary replacements for PLPA modules and is
searched first.
JES JOB JCL Procedure Library
JES2 JCL Procedure Librares are searched for JOB and STC PROCs
//PROC00 DD DSN=SYS1.PROCLIB,DISP=SHR
// DD DSN=SYS3.PROD.PROCLIB,DISP=SHR
//PROC01 DD DSN=SYS1.PROC2,DISP=SHR
...
//PROCnn DD DSN=SYS1.LASTPROC,DISP=SHR
...
JOB JCL can have personal JCL Procedure Libraries search first
//MYJOB JOB
//MYLIBS JCLLIB ORDER=(MY.PROCLIB.JCL,YOUR.PROCLIB.JCL)
//S1 EXEC PROC=MYPROC1
...
System Symbols
System symbols allow the use of a shared parmlib by two or more systems
Each symbol has a name which can be used in various places and then substituted at IPL time
Major uses are indirect cataloging and substituting system specific data sets such as the page
data sets
Professional Manuals
Unit summary
Having completed this unit, you should be able to:
•
Describe IPL process
•
Describe IPL device and LOADPARM device
•
Describe Support Element and HMC
•
Describe System Parameters/Definitions
•
Determine IPL and LOAPARM device using MVS commands
•
Determine LOADPARM member read at IPL time
•
Determine parameter libraries read at IPL time
•
Determine parameter library members read at IPL time
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