subprocess Popen not working via crontab

[nitin23c]

Hey All,

Okay , I'm gonna admit this issue has me completely stumped and i'm at my wits end.

Below is the code that has been troubling me and i have tried all the things i know or could have googled.

session = Popen(['dgmgrl','username/password@dbname','stop observer', '-logfile', '/u01/app/oracle/broker/fsfo_mydg.log'],stdout=PIPE, stderr=PIPE, cwd=r'/u01/app/oracle/product/11.2.0/db1/bin/')
output,error = session.communicate()
if session.returncode != 0:
    raise RuntimeError("broker command failed with %s stdout %r stderr %r" % (session.returncode, output, error))
else:
    print >> file, "The stdout is :\n %s" % output
    file.flush()

So while trying to execute above directly on the terminal , it executes perfectly , But it simply does not runs and throws below error when scheduled to run from crontab.

Error:
OSError >  2
OSError >  No such file or directory
OSError >  None

or 

Error:
RuntimeError >  broker command failed with -11 stdout '' stderr ''
Successfully sent email at 2017-03-15 09:32:10.226847

and i have tried all combinations of command formatting.

Please help.

Regards,
Nitin