Restart:-

Restarting a program which is abounded at some step-step0020 (step0019 are executed already )

RESTART= stepname

When job is submitted first it is going to check for restart.

If temp dataset is created in step0018 after abounding, the temp dataset is refreshed if restart is coded as step0020, it gives error: Temp dataset not available so code RESTART = step0018.

Note :- restart must be always coded in the spool only not in the jcl peg.