Red Hat Directory Server 8.0 Administrator's Guide

NOTE
The Directory Server does not have to be started for the subagent to be started.
To stop your subagent, you must use the kill command against its process ID. Your subagent
will print its process ID in its logfile, or you can run ps -ef | grep ldap-agent to find the
process ID.
3.3. Testing the Subagent
To test your subagent, use any SNMP client tools to query the master agent. Net-SNMP
contains simple command-line utilities such as snmpwalk and snmpget. In order for these tools
to use variable names for queries, configure them to load the Directory Server's MIB file. The
Directory Server's MIB file, redhat-ds.mib, is located in /usr/share/dirsrv/mibs on Red Hat
Enterprise Linux and Solaris and in /opt/dirsrv/share/mibs on HP-UX. There are some
additional common required MIB files in this mibs directory if you do not already have them with
your MIB tools.
The MIB file is not needed for the subagent to operate; it is only required for any SNMP client
application to use variable names instead of numeric OIDs to refer to the monitored information
provided by the subagent.
Each monitored server instance uses its port number as an index to identify that particular
Directory Server instance. For example, querying for the dsEntityName.389 SNMP variable
returns the variable value for a server running on port 389, assuming that instance exists and is
being monitored by the subagent.
For details on configuring and using the Net-SNMP command-line tools, check out the
Net-SNMP website, http://www.net-snmp.org.
4. Configuring SNMP Traps
An SNMP trap is essentially a threshold which triggers a notification if it is encountered by the
monitored server. To use traps, the master agent must be configured to accept traps and do
something with them. For example, a trap can trigger an email notification for an administrator of
the Directory Server instance stops.
The subagent is only responsible for sending the traps to the master agent. The master agent
and a trap handler must be configured according to the documentation for the SNMP master
agent you are using.
Traps are accompanied by information from the Entity Table, which contains information
specific to the Directory Server instance, such as its name and version number. The Entity
Chapter 14. Monitoring Directory Server Using SNMP
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