SSM commands are not working in OPS/MVS
SSMCNTL in disabled
To start using the SSM commands .You will first need to Enable and auto-enable the rule 'SSMCNTL' .You can find this rule in CCLXRULM library .
Once the rule is enable you can try issung commands.
/SSM HELP : You will find all SSM valid commands that you can issue.