User manual

C HAPTER 15 | Basic Administration Protocols
Link Layer Discovery Protocol
– 206 –
ES-2000 Series
SETTING LLDP TIMING
ATTRIBUTES
Use the Administration > LLDP (Configure Global) page 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.
PARAMETERS
These parameters are displayed:
◆ 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