Donald K. Burleson
Oracle Utilities Tips
The OEMCTL Utility
The next monitoring utility that will be explained is used as part of Oracle
Enterprise Manager (OEM) to provide many shared services for managing
databases. OEM is the database management solution provided by Oracle
Corporation. The OEMCTL utility manages the Oracle Management Server (OMS)
used by OEM.
The OMS manages back-end application logic and stores information in the OEM
repository. The functionality provided by the management server includes
events, jobs, data sharing, and reports. The OMS serves as the middle tier
between the management pack GUIs and the databases being managed. Multiple
OMSs can exist in order to evenly distribute heavy workloads across this
middle tier, although only one OMS can exist per node.
The repository used by OMS is simply a set of tables in a particular
instance that support the management pack (Change, Diagnostics, Tuning)
components of OEM.
Many commands are available from the oemctl executable at the OS level that
help the DBA to manage the OMS. The following command will start the OMS:
oemctl start oms
If already running, the feedback from the command will respond, “The
requested service has already been started.”
The OMS is a Java application and when started, the Java Runtime (JRE) will
be loaded into memory and consume approximately 40MB of RAM.
The method used to see if an OMS server is up and running is similar to the
method in which a network administrator would check for TCP/IP communication
to a remote host – ping.
oemctl ping oms
The ping command reports “the management server is running”. To get a more
detailed status of the OMS, the status command can be executed. This
command, along with the stop command, requires the OMS Administrator’s
username and password in order to work. Optionally, the host name of the
machine containing the OMS process can be specified if not the local
machine. The default OMS Administrator username is password is sysman/oem_temp.
oemctl status oms <EM Username>/<EM Password>[@<OMS-hostname>]
This command requires the OMS administrator username and password. If not
supplied, a Java application window will pop up and prompt for the username
and password, as shown in Figure 5.3 below. Therefore, it is critical that
the machine that initiates the command supports Java, otherwise the command
will hang. For instance, if an attempt is made to obtain the status of the
OMS by telnetting from a Windows machine to a UNIX box, the command will
hang because the Java GUI application is unable to load. Again, this only
applies when not specifying the username and password on the command line.
The result of the oemctl status command is shown below. Note the additional
information that status provides over the ping command.
The Oracle Management Server on host [moorepc] is functioning properly.
The server has been up for 0 00:02:45.406
Target database session count: 0 (session sharing is off)
Operations queued for processing: 1
Number of OMS systems in domain: 1 (moorepc)
Number of administrators logged in: 1
Repository session pool depth: 15
Repository session count: 7 in-use and 4 available, pool
To learn more about these techniques, see the book "Advanced
Oracle Utilities: The Definitive Reference".
You can buy it
the publisher and get instant access to the code depot of
||Need an Oracle Health Check?
Does your boss blame you for an Oracle performance problem?
Need to prove that your database is properly optimized?
BC Oracle performance guru's can quickly verify every aspect of your
Oracle database and provide a complete certification that your database
is fully optimized.