Database Reference
In-Depth Information
Oracle Management Agent
The Oracle Management Agent is responsible for sending metrics and pending alerts for hosts on which it is installed.
To provide high availability, the following features should be enabled for the agent:
•
Enable the agent to start automatically on OS boot up. This should be configured
automatically after running the
root.sh
script.
Install the agent on redundant storage. This includes a RAID-configured storage back end.
•
•
Configure restart parameters for the agent watchdog process. The watchdog process is
responsible for restarting the agents based on the following environment variables:
•
EM_MAX_RETRIES
indicates the maximum number of times the watchdog process will
attempt to restart the agent within the
EM_MAX_RETRY_WINDOW
. The default is set to 3.
•
EM_RETRY_WINDOW
indicates the time interval that is used with
EM_MAX_RETRIES
before
trying to start the management agent. The default is set to 600 seconds.
After installing the Enterprise Manager agent, the
<AGENT_HOME>/root.sh
script should be executed.
This will create the following scripts on Linux and some Unix operating systems that control the startup of the
management agent.
/etc/init.d/gcstartup
•
/etc/init/gcstartup
•
/etc/rc.d/init.d/gcstartup
If these files are not present, make sure the
<AGENT_HOME>/root.sh
script has been executed.
Loss or corruption of the agent will result in loss of monitoring and metric data uploads for its associated targets.
Likewise, if the agent is down, targets will not be able to communicate with the management server, resulting in loss
of manageability.
•
Management Repository
The repository is the persistent store for monitoring data uploaded by agents. It stores metrics and configuration
data from all monitored targets. Loss of the repository will result in management server failure. It is recommended
to enable database high-availability features such as Real Application Clusters (RAC) or RAC One Node,
Automatic Storage Management (ASM) for data file storage (depending on redundancy levels and back-end RAID
configuration),and Data Guard for the repository. Additionally, the management service should be configured to use
the Single Client Access Name (SCAN) and a nondefault RAC service name if the repository is configured as a RAC
database. The following is an example of configuring the management service for use with a RAC database:
emctl config oms -store_repos_details -repos_conndesc "
(DESCRIPTION= (ADDRESS=(PROTOCOL=TCP)
(HOST=emrep-scan.example.com)(PORT=1521) )
(CONNECT_DATA=(SERVER=DEDICATED) (SERVICE_NAME = emrep)))"
-repos_user sysman
Figure
13-2
shows an example of an OMS configured with a RAC repository database using the SCAN name.
For additional details on configuring SCAN, see the
Oracle Clusterware Administration and Deployment Guide 11g
Release 2 (11.2)
.
