Korenix JetNet 5228G Series, User Manual

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Configuring the Switch
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3
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