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Snmp traps, Sending snmp traps to an snmp trap receiver – D-Link DFL-2500 User Manual

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Note

The syslog server may have to be configured to receive log messages from
NetDefendOS. Please see the documentation for your specific Syslog server software
in order to correctly configure it.

2.2.3.2. SNMP Traps

The SNMP protocol

Simple Network Management Protocol (SNMP) is a means for communicating between a Network
Management System (NMS) and a managed device. SNMP defines 3 types of messages: a Read
command for an NMS to examine a managed device, a Write command to alter the state of a
managed device and a Trap which is used by managed devices to send messages asynchronously to
an NMS about a change of state.

SNMP Traps in NetDefendOS

NetDefendOS takes the concept of an SNMP Trap one step further by allowing any event message
to be sent as an SNMP trap. This means that the administrator can set up SNMP Trap notification of
events that you consider significant for the operation of a network.

The file DFLNNN-TRAP.MIB (where NNN indicates the model number of the firewall) is provided
by D-Link and defines the SNMP objects and datatypes that are used to describe an SNMP Trap
received from NetDefendOS.

Note

There is a different MIB file for each model of D-Link Firewall. Make sure that the
correct file is used.

For each D-Link Firewall model there is one generic trap object called DLNNNosGenericTrap, that
is used for all traps (where NNN indicates the model number). This object includes the following
parameters:

System - The system generating the trap

Severity - Severity of the message

Category - What NetDefendOS subsystem is reporting the problem

ID - Unique identification within the category

Description - A short textual description

Action - What action is NetDefendOS taking

This information can be cross-referenced to the Log Reference Guide.

Note

NetDefendOS sends SNMP Traps which are based on the SNMPv2c standard as
defined by RFC1901, RFC1905 and RFC1906.

Example 2.12. Sending SNMP Traps to an SNMP Trap Receiver

To enable generation of SNMP traps for all events with a severity greater than or equal to Alert to an SNMP trap
receiver with an IP address of 195.11.22.55, follow the steps outlined below:

2.2.3. Event Message Distribution

Chapter 2. Management and Maintenance

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