13 Oracle Enterprise Manager Management Agent

13.1 Overview

The Oracle Management Agent runs jobs and events sent by the Oracle Enterprise Manager and can start up and shut down a database. It can function regardless of the status of the network connection, and it can run even if the database is down. It enables the database abministrator to monitor and control a database from a central location on the network.

The Management Agent is controlled using a command in the z/OS UNIX System Services shell environment. Currently, it is the only component of Oracle Enterprise Manager that is implemented for Oracle Database for z/OS. For more information on the Management Agent, refer to the Oracle Enterprise Manager Book Set.

13.2 Configuring the Management Agent

The Management Agent is installed with Oracle Database for z/OS. Oracle Universal Installer also configures most of the required parameters.

For the Management Agent to work correctly on z/OS, the following changes must be made to the system:

• The Mangement Agent is a multi-threaded application which starts and stops numerous threads during its operation. The BPX parameter file needs to be altered and activated on your system, as follows:

  MAXTHREADS(20000)
  
  

  BPX parameters are set in the SYS1.PARMLIB(BPXxxx).

• The nmo and nmp executable needs to have its extended attributes set as follows:

  extattr +p nmo
  extattr +p nmb
  
  

  This is because the executable uses the c function __passwd to verify a user and password before attempting to execute a command on behalf of a user (for example, database shutdown and startup).

• The ownership of the em* executables in the ORACLE_HOME/bin directory must be set to that of the user who will run the Management Agent.

To complete the configuration, the following three files need additional customization:

• The emd.properties file in the sysman/config directory

  This file contains the global variables for the Management Agent. For most installations, the following two parameters need to be modified:

  • REPOSITORY_URL=http://host:port/em/upload/

    This is the location of the Oracle Management Service where you want the Management Agent to register.

  • EMD_URL=http://local_host:port/emd/main/

    This is the location and port where you want the Management Agent to listen for communications from clients.

• The targets.xml file in the sysman/emd directory

  This file contains the information about the local system and its database instances. It is in XML format and needs to be customized. Although the Management Agent attempts to configure this file, z/OS differences may not permit it to do so.

  The following is a sample targets.xml file:

<?xml version = "1.0"?>
<Targets AGENT_SEED="153361320">
 <Target TYPE="oracle_emd" NAME="local_host:port" VERSION="1.0"
 <Target TYPE="host" NAME="local_host" VERSION="1.0"/>
 <Target TYPE="oracle_database" NAME="DB_sid" VERSION="1.0">
  <Property NAME="MachineName" VALUE="local_host"/>
  <Property NAME="Port" VALUE="DB_port"/>
  <Property NAME="SID" VALUE="DB_sid"/>
  <Property NAME="ConnectDescriptor" VALUE="(DESCRIPTION=(ADDRESS_LIST=(ADDRESS=(PROTOCOL=TCP)(local_host)(PORT=DB_port)))(CONNECT_DA TA=(SID=DB_sid)))"/>
  <Property NAME="OracleHome" VALUE="oracle_home"/>
  <Property NAME="UserName" VALUE="DBSNMP"/>
  <Property NAME="password" VALUE="password" ENCRYPTED="FALSE"/>
  <Property NAME="Role" VALUE="NORMAL"/>
 </Target>
</Targets>

Variables for the previous example are defined as follows:

The following variables for the previous example can be obtained from the tnsnames.ora file for the instance being monitored. They are defined as follows:

• The /var/opt/oratab file

  This file should contain one line for every database instance being configured, as in the following example:

  instance_name:ORACLE_HOME:N
  
  

  In the previous example, instance_name is the name of the database instance, and ORACLE_HOME is the Oracle home where the Oracle database software is located.

13.3 Controlling the Management Agent

You use the emctl command to control the Management Agent. For a description of this and other Management Agent commands, refer to the Oracle Enterprise Manager Advanced Configuration manual.

To issue this command, first log in to the z/OS UNIX System Services environment as the user who owns the Management Agent code. This user also needs DBA privileges.

Set up environment variables in the ENV file located in the Oracle home directory.

To start the Management Agent, use the following command:

$ emctl start agent

To query the status of agent, use the following command:

$ emctl status agent

To upload the information of Management Agent to the Management Service, use the following command:

$ emctl upload

The host information appears at the Management Service location. you need to upload the information only if the status of the agent is not automatically updated.

To stop the Management Agent, use the following command:

$ emctl stop agent

The log files and tracing information will be written to the ORACLE_HOME/sysman/log file.