HP ProCurve 9304M Installation And Configuration Manual page 119

virtual routing interface that is the source for the traps. The HP device then uses the lowest-numbered IP address
configured on the port or interface as the source IP address in the SNMP traps sent by the device.
Identifying a single source IP address for SNMP traps provides the following benefits:
• If your trap receiver is configured to accept traps only from specific links or IP addresses, you can use this
feature to simplify configuration of the trap receiver by configuring the HP device to always send the traps
from the same link or source address.
• If you specify a loopback interface as the single source for SNMP traps, SNMP trap receivers can receive
traps regardless of the states of individual links. Thus, if a link to the trap receiver becomes unavailable but
the receiver can be reached through another link, the receiver still receives the trap, and the trap still has the
source IP address of the loopback interface.
To specify a port, loopback interface, or virtual routing interface whose lowest-numbered IP address the HP device
must use as the source for all SNMP traps sent by the device, use the following CLI method.
USING THE CLI
To configure the device to send all SNMP traps from the first configured IP address on port 4/11, enter the
following commands:
HP9300(config)# snmp-server trap-source ethernet 4/11
HP9300(config)# write memory
Syntax: snmp-server trap-source loopback <num> | ethernet <portnum> | ve <num>
The <num> parameter is a loopback interface or virtual routing interface number. If you specify an Ethernet port,
the <portnum> is the port's number.
To specify a loopback interface as the device's SNMP trap source, enter commands such as the following:
HP9300(config)# int loopback 1
HP9300(config-lbif-1)# ip address 10.0.0.1/24
HP9300(config-lbif-1)# exit
HP9300(config)# snmp-server trap-source loopback 1
The commands in this example configure loopback interface 1, assign IP address 10.00.1/24 to the loopback
interface, then designate the interface as the SNMP trap source for this Routing Switch. Regardless of the port
the HP device uses to send traps to the receiver, the traps always arrive from the same source IP address.
USING THE WEB MANAGEMENT INTERFACE
You cannot configure a trap source using the Web management interface.
Setting the SNMP Trap Holddown Time
When an HP device starts up, the software waits for Layer 2 convergence (STP) and Layer 3 convergence
(OSPF) before beginning to send SNMP traps to external SNMP servers. Until convergence occurs, the device
might not be able to reach the servers, in which case the messages are lost.
By default, an HP device uses a one-minute holddown time to wait for the convergence to occur before starting to
send SNMP traps. After the holddown time expires, the device sends the traps, including traps such as "cold
start" or "warm start" that occur before the holddown time expires.
You can change the holddown time to a value from one second to ten minutes.
USING THE CLI
To change the holddown time for SNMP traps, enter a command such as the following at the global CONFIG level
of the CLI:
HP9300(config)# snmp-server enable traps holddown-time 30
The command in this example changes the holddown time for SNMP traps to 30 seconds. The device waits 30
seconds to allow convergence in STP and OSPF before sending traps to the SNMP trap receiver.
Syntax: [no] snmp-server enable traps holddown-time <secs>
Configuring Basic Features
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