Reason: Agent upgraded to 10.2.0.4 or database upgraded to 10.2.0.4, which trigger bug in health check metric on Linux x86-x64
Solutions: Choose Plan A or Plan B.
Plan A: Upgrade the Grid Agent to 10.2.0.4 version.
1. Shutdown the monitored target database.
2. Rename the $RDBMS_HOME/dbs/hc_<sid>.dat file to $RDBMS_HOME/dbs/hc_<sid>.old
3. Apply Patch 5872000 on the database Oracle Home
4. Restart the database
5. Verify that the $RDBMS_HOME/dbs/hc_<sid>.dat is newly created with a size of 1544 bytes.
6. Verify that the 10.2.0.4 Agent can now collect the Healthcheck metric without any issues now.
Plan B: disable the Health Check Metric Collection in Grid Control 10.2
go to Grid Control -> database -> Metric and Policy , modify all 7 metrics belong to Health Check metric category:
Instance Status, Instance State, Maintenance, Mounted,State Description,Unavailable,Unmounted.