Connectivity Guide
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SNMP Traps
SNMP is frequently used to monitor systems for fault conditions such as temperature violations, hard drive failures. Management
applications can monitor for these conditions by polling the appropriate OIDs with the Get command and analyzing the returned
data. This method has its drawbacks. If it is done frequently, signicant amounts of network bandwidth can be consumed. If it is
done infrequently, the response to the fault condition may not occur in a timely fashion. SNMP traps avoid these limitations of the
polling method.
An SNMP trap is an asynchronous event indicating that something signicant has occurred. This is analogous to a pager receiving an
important message, except that the SNMP trap frequently contains all the information needed to diagnose a fault.
Two drawbacks to SNMP traps are that they are sent using UDP, which is not a guaranteed delivery mechanism, and that they are
not acknowledged by the receiver.
An SNMP trap message contains the trap’s enterprise OID, the agent IP address, a generic trap ID, the specic trap ID, a time stamp,
and zero or more variable bindings (varbinds). The combination of an enterprise OID and a specic trap ID uniquely identies each
Server Administrator-dened trap. A varbind consists of an OID and its value and provides additional information about the trap.
In order for a management system to receive SNMP traps from a managed system, the node must be congured to send traps to
the management system. Trap destination conguration depends on the operating system. When this conguration is done, a
management application on the management system can wait for traps and act on them when received.
NOTE: For the list of storage management alerts and storage management messages, see the
Dell OpenManage Server
Administrator Messages Reference Guide
available on the Dell Support site at dell.com/openmanagemanuals navigate to
OpenManage Software and select the version required.
For a list of traps supported by the Remote Access Controller, see RAC Traps, BMC Traps, iDRAC7 and iDRAC8 Traps.
Understanding Trap Severity
Traps often contain information about values recorded by probes or sensors. Probes and sensors monitor critical components for
values such as amperage, voltage, and temperature. When an event occurs on your system, the Server Administrator sends
information about one of the following event types to the system management console:
• Information/Informational—An event that describes the successful operation of a unit, such as a power supply turning on or a
sensor reading returning to normal.
• Warning — An event that is not necessarily signicant, but may indicate a possible future problem, such as crossing a warning
threshold.
• Critical/Error — A signicant event that indicates actual or imminent loss of data or loss of function, such as crossing a failure
threshold or a hardware failure.
RAC Traps
This section describes the traps that are generated by the SNMP agent of the Remote Access Controller (RAC). All the enterprise-
specic traps documented in this section belong to the MIB enterprise identied by OID 1.3.6.1.4.1.674.10892.2 and are sent with all
the trap variables documented in the section. The trap variables are sent in the order in which they are listed.
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