To start the Oracle Enterprise Manager/Grid Control components in version 11g (11.1.0.1)
$ cd /bin; ./emctl start oms
$ cd /bin; ./emctl start agent
Where OMS_HOME is /u01/weblogic/oms11g and AGENT_HOME is /u01/weblogic/agent11g
Note: This will also start weblogic too

To stop Oracle Enterprise Manager version 11g (11.1.0.1)
$ cd /bin; ./emctl stop agent
$ cd /bin; ./emctl stop oms -all
Where OMS_HOME is /u01/weblogic/oms11g and AGENT_HOME is /u01/weblogic/agent11g
Note: This will also stop weblogic too

Check if any process not terminated and still running, if any found terminate the process
$ ps -ef | grep emagent
$ ps -ef | grep oms11g
$ ps -ef | grep gc_inst

To check OMS Status
/u01/weblogic/oms11g/bin $ ./emctl status oms
Oracle Enterprise Manager 11g Release 1 Grid Control
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