Hi Reza,
Please try the sapcontrol command to start the system
you can find the sap control command in below link
http://help.sap.com/saphelp_nwpi711/helpdata/en/49/9a15525b20423ee10000000a421938/content.htm
also please check the sapservices at /usr/sap/ location it should present and shjould have correct entry.
Best Regards,
Atul
