Looking through log files in $ORACLE_HOME/machine_SID/sysman/log i see:
2011-03-12 02:57:37 Thread-1 Starting Agent 10.1.0.6.0 from /u01/app/oracle/product/10.2.0.1/db_1 (00701)
2011-03-12 02:57:41 Thread-1 EMAgent started successfully (00702)
2011-03-12 14:57:20 Thread-6963 Disable collector (00406)
What is that disable collector and what impact does it have. My dbconsole is not running and it should be.