Technical data
BLADE OS 5.1 Application Guide
90
Chapter 6: Link Layer Discovery Protocol BMD00136, November 2009
Time-to-Live for Transmitted Information
The transmitted LLDP information is held by remote systems for a limited time. A time-to-live
parameter allows the switch to determine how long the transmitted data should be held before it
expires. The hold time is configured as a multiple of the configured transmission interval.
where multiplier is a value between 2 and 10. The default value is 4, meaning that remote systems
will hold the port’s LLDP information for 4 x the 30-second msgtxint value, or 120 seconds,
before removing it from their MIB.
Trap Notifications
If SNMP is enabled on the G8000 (see “Using SNMP” on page 22), each port can be configured to
send SNMP trap notifications whenever LLDP transmissions are sent. By default, trap notification
is disabled for each port. The trap notification state can be changed using the following commands
(Interface Port mode):
In addition to sending LLDP information at scheduled intervals, LLDP information is also sent
when the G8000 detects relevant changes to its configuration or status (such as when ports are
enabled or disabled). To prevent the G8000 from sending multiple trap notifications in rapid
succession when port status is in flux, a global trap delay timer can be configured.
The trap delay timer represents the minimum time permitted between successive trap notifications
on any port. Any interval-driven or change-driven trap notices from the port will be consolidated
until the configured trap delay expires.
The minimum trap notification interval can be configured using the following command:
where interval is the minimum number of seconds permitted between successive LLDP
transmissions on any port. The range is 1 to 3600. The default is 5 seconds.
>> # lldp holdtime-multiplier <multiplier>
>> # lldp trap-notification (Send SNMP trap notifications)
or
>> # no lldp trap-notification (Do not send trap notifications)
>> # lldp trap-notification-interval <interval>