H3C Technologies H3C WX5500E Series Access Controllers - Manual (Page 226)

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Item Description
TTL Multiplier
Set the TTL multiplier.
The TTL TLV carried in an LLDPDU determines how long the device information
carried in the LLDPDU can be saved on a recipient device. You can configure the
TTL of locally sent LLDPDUs to determine how long information about the local
device can be saved on a neighbor device by setting the TTL multiplier. The TTL is
expressed as TTL multiplier × LLDPDU transit interval.
When you configure the TTL multiplier, follow these guidelines:
• If the product of the TTL multiplier and the LLDPDU transmit interval is greater
than 65535, the TTL carried in transmitted LLDPDUs takes 65535 seconds.
• Because the maximum TTL allowed by CDP is 255 seconds, you must make sure
the product of the TTL multiplier and the LLDPDU transmit interval is less than 255
seconds for CDP-compatible LLDP to work properly with Cisco IP phones.
Trap Interval
Set the minimum interval for sending traps.
With the LLDP trapping function enabled on a port, traps are sent out of the port to
advertise the topology changes detected over the trap interval to neighbors. By
tuning this interval, you can prevent excessive traps from being sent when topology
is instable.
Reinit Delay
Set initialization delay for LLDP-enabled ports.
Each time the LLDP operating mode of a port changes, its LLDP protocol state
machine re-initializes. To prevent LLDP from being initialized too frequently at times
of frequent operating mode change, initialization delay is introduced. With this
delay mechanism, a port must wait for the specified interval before it can initialize
LLDP after the LLDP operating mode changes.
Tx Delay
Set LLDPDU transmit delay.
With LLDP enabled, a port advertises LLDPDUs to its neighbors both periodically
and when the local configuration changes. To avoid excessive number of LLDPDUs
caused by frequent local configuration changes, an LLDPDU transmit delay is
introduced. After sending an LLDPDU, the port must wait for the specified interval
before it can send another one.
LLDPDU transmit delay must be less than the TTL to make sure the LLDP neighbors can
receive LLDPDUs to update information about the device you are configuring before it
is aged out.
Tx Interval
Set the LLDPDU transmit interval.
If the product of the TTL multiplier and the LLDPDU transmit interval is greater than
65535, the TTL carried in transmitted LLDPDUs takes 65535 seconds. The likelihood
exists that the LLDPDU transmit interval is greater than TTL. You should avoid the
situation, because the LLDP neighbors will fail to receive LLDPDUs to update
information about the device you are configuring before it is aged out.
Displaying LLDP information for a port
1. Select Network > LLDP from the navigation tree.
By default, the Port Setup tab is displayed.
2. On the port list, click a port name to display its LLDP information at the lower half of the page.
By default, the Local Information tab is displayed.
Table 80 describes the fields.