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Cisco Intrusion Prevention System Sensor CLI Configuration Guide for IPS 7.2
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Chapter 15 Configuring SNMP
Configuring SNMP
You can configure the sensor to send SNMP traps. SNMP traps enable an agent to notify the management
station of significant events by way of an unsolicited SNMP message.
Trap-directed notification has the following advantage—if a manager is responsible for a large number
of devices, and each device has a large number of objects, it is impractical to poll or request information
from every object on every device. The solution is for each agent on the managed device to notify the
manager without solicitation. It does this by sending a message known as a trap of the event.
After receiving the event, the manager displays it and can take an action based on the event. For instance,
the manager can poll the agent directly, or poll other associated device agents to get a better
understanding of the event.
Note
Trap-directed notification results in substantial savings of network and agent resources by eliminating
frivolous SNMP requests. However, it is not possible to totally eliminate SNMP polling. SNMP requests
are required for discovery and topology changes. In addition, a managed device agent cannot send a trap
if the device has had a catastrophic outage.
Configuring SNMP
Caution
To have the sensor send SNMP traps, you must also select request-snmp-trap as the event action when
you configure signatures.
Configure general SNMP parameters in the service notification submode.
The following options apply:
•
default—Sets the value back to the system default setting.
•
enable-set-get {true | false}—Enables the gets and sets of object iden tifiers (OIDs).
•
no—Removes an entry or selection setting.
•
read-only-community���Specifies the read-only community name for the SNMP agent. The default
is public.
•
read-write-community—Specifies the read-write community name for the SNMP agent. The
default is private.
•
snmp-agent-port—Specifies the port the SNMP agent will listen on. The default SNMP port
number is 161.
•
snmp-agent-protocol—Specifies the protocol the SNMP agent will communicate with. The default
protocol is UDP.
•
system-contact—Specifies the contact information for this sensor. The system-contact option
modifies the SNMPv2-MIB::sysContact.0 value.
•
system-location—Specifies the location of the sensor. The system-location option modifies the
SNMPv2-MIB::sysLocation.0 value.