Installation manual

3-208
SIGNAMAX LLC • www.signamax.eu
Setting LLDP Timing Attributes
Use the LLDP Configuration screen to set attributes for general functions such as globally
enabling LLDP on the switch, setting the message ageout time, and setting the frequency
for broadcasting general advertisements or reports about changes in the LLDP MIB.
Command Attributes
• LLDP – Enables LLDP globally on the switch. (Default: Enabled)
• Transmission Interval – Configures the periodic transmit interval for LLDP
advertisements. (Range: 5-32768 seconds; Default: 30 seconds)
This attribute must comply with the following rule:
(Transmission Interval * Hold Time Multiplier) ≤
65536, and
Transmission Interval >= (4 * Delay Interval)
• Hold Time Multiplier – Configures the time-to-live (TTL) value sent in LLDP
advertisements as shown in the formula below. (Range: 2-10; Default: 4)
The time-to-live tells the receiving LLDP agent how long to retain all information
pertaining to the sending LLDP agent if it does not transmit updates in a timely manner.
TTL in seconds is based on the following rule:
(Transmission Interval * Holdtime Multiplier) ≤
65536.
Therefore, the default TTL is 4*30 = 120 seconds.
• Delay Interval – Configures a delay between the successive transmission of
advertisements initiated by a change in local LLDP MIB variables.
(Range: 1-8192 seconds; Default: 2 seconds)
The transmit delay is used to prevent a series of successive LLDP transmissions during
a short period of rapid changes in local LLDP MIB objects, and to increase the
probability that multiple, rather than single changes, are reported in each transmission.
This attribute must comply with the rule: (4 * Delay Interval) ≤
Transmission Interval
• Reinitialization Delay – Configures the delay before attempting to re-initialize after
LLDP ports are disabled or the link goes down. (Range: 1-10 seconds; Default: 2
seconds)
When LLDP is re-initialized on a port, all information in the remote systems LLDP MIB
associated with this port is deleted.
• Notification Interval – Configures the allowed interval for sending SNMP notifications
about LLDP MIB changes. (Range: 5-3600 seconds; Default: 5 seconds)
This parameter only applies to SNMP applications which use data stored in the LLDP
MIB for network monitoring or management.
Information about changes in LLDP neighbors that occur between SNMP notifications is
not transmitted. Only state changes that exist at the time of a notification are included in
the transmission. An SNMP agent should therefore periodically check the value of
lldpStatsRemTableLastChangeTime to detect any lldpRemTablesChange
notification-events missed due to throttling or transmission loss.