Mainframe Important Terms:
MAINFRAME -> large computer, industrail application, insurance,
banking, finance, pharmacy,....
TSO -> time sharing option, it interacts with os on the mainframe
computer.
OPERATING SYSTEM - z/OS IBM MAINFRAME COMPUTER.
z/OS ZERO DOWNTIME OPERATING SYSTEM
FRONT END -> CICS (CUSTOMER INFORMATION CONTROL SYSTEM)
BACK END -> DB2, IMS/DB
FILE SYSTEM -> VSAM
APPLICATION LANGUAGE -> COBOL, PL\1(PLBAVAN), ASSEMBLER, REXX
SCRIPTING LANGUAGE -> JCL (JOB CONTROLLING LANGUAGE). IN ORDER TO
execute job in batch mode.
ISPF -> INTERACTIVE SYSTEM PRODUCTIVITY FACILITY.
USER ID -> max 8 character. that is 8 bytes. a634923
PASSWORD -> max 8 character. same
EMULATOR -> TN3270, humming bird, vista,....these are used to connect
mainframe. in order to interact with mainframe system.
QUALIFIER -> max of 8 alphanumeric. $#@
first character should be alphabet. to seperate qualifier we use period.
SEQUENTIAL DATASET -> PS (PHYSICAL SEQUENTIAL)
PARTIONED DATA SET -> FOLDER (MEMBERS)
DASD -> the hard disk which is collection of volumes is called dasd.
DIRECT ACCESS STORAGE DEVICE.
TAPES -> IT IS A MAGNETIC TAPES WHICH IS USED TO BACKUP THE DATASET OR
ARCHIEVE OLD DATASETS.
CATALOG -> It is the master register which is stores the details of
the dataset and pointers to the volume in which the dataset resides.
While creating a dataset we need not to give the volume serials.
MVS will allocate volume serials automatically. Volume details for the
datasets.
VTOC -> VOLUME TABLE OF CONTENTS. it has the info of the dasd storage
like dataset resides in it, free space available of each volume,etc
whenever a new dataset is create/deleted a entry is made/removed in VTOC
SMS - STORAGE MANAGEMENT SUBSYSTEM. The purpose of SMS is to do analysis
the volumes on the mainframe server and suggest the best volume for
allocation of the dataset to MVS. With the help of SMS, MVS will do
allocation efficiently.
NON-SMS -> In earlier days NON-SMS is used. Later version SMS is used.
UNCATALOG -> It is managed in NON-SMS environment. We can remove the
link between catalog and volume. If any user needs to access the dataset
he needs to provide the volume serial of that dataset.
Create PDS:
from ISPF panel select option 3 (utilities)
from utility selection panel, select option 2 (data set)
now i am going to allocate a new dataset so i am giving "A" in the
option.
in name file we need to give the dataset name.
Average record unit
Primary quantity -> It will take value based on space unit.
Secondary quantity -> It will get allocate when it is needed
Directory blocks -> here we need to give value based on that we can
add member
Record format -> either FB or VB
Record length -> we need to give the record length value
Block size -> it will get calculated based on record length
Create PS:
from ISPF panel select option 3 (utilities)
from utility selection panel, select option 2 (data set)
now i am going to allocate a new dataset so i am giving "A" in the
option.
in name file we need to give the dataset name.
Average record unit
Primary quantity -> It will take value based on space unit.
Secondary quantity -> It will get allocate when it is needed
Directory blocks -> for PS we need to give value as "0"
Record format -> either FB or VB
Record length -> we need to give the record length value
Block size -> it will get calculated based on record length
