H3C Technologies H3C S12500 Series Switches - Manual (Page 239)

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By setting the TTL multiplier, you can configure the TTL of locally sent LLDPDUs, which determines how
long information about the local device can be saved on a neighboring device. The TTL is expressed by
using the following formula:
TTL = Min (65535, (TTL multiplier × LLDP frame transmission interval))
As the expression shows, the TTL can be up to 65535 seconds. TTLs greater than 65535 will be rounded
down to 65535 seconds.
Configuration restrictions and guidelines
• Both the LLDP frame transmission interval and delay must be smaller than the TTL to make sure LLDP
neighbors can receive LLDP frames to update information about the switch you are configuring
before it is aged out.
• H3C recommends that you set the LLDP frame transmission interval to be no smaller than four times
the LLDP frame transmission delay.
• If the LLDP frame transmission delay is greater than the LLDP frame transmission interval, the switch
uses the LLDP frames transmission delay as the transmission interval.
Configuration procedure
To set related LLDP parameters:
Step Command Remarks
1. Enter system view. system-view N/A
2. Set the TTL multiplier. lldp hold-multiplier value
Optional.
The default setting is 4.
3. Set the LLDP frame
transmission interval.
lldp timer tx-interval interval
Optional.
The default setting is 30 seconds.
4. Set LLDP frame transmission
delay.
lldp timer tx-delay delay
Optional.
The default setting is 2 seconds.
5. Set the number of LLDP frames
sent each time fast LLDP frame
transmission is triggered. lldp fast-count count
Optional.
The default setting is 3.
Configuring the encapsulation format for LLDP frames
LLDP frames can be encapsulated the following formats:
• Ethernet II—With Ethernet II encapsulation configured, an LLDP port sends LLDP frames in Ethernet
II frames and processes an incoming LLDP frame only when it is Ethernet II encapsulated.
• SNAP—With SNAP encapsulation configured, an LLDP port sends LLDP frames in SNAP frames and
processes an incoming LLDP frame only when it is SNAP encapsulated.
By default, LLDP frames are encapsulated in Ethernet II frames. If the neighbor switches encapsulate LLDP
frames in SNAP frames, configure the encapsulation format for LLDP frames as SNAP to guarantee
normal communication with the neighbors.
To configure the encapsulation format for LLDP frames as SNAP: