3Com S7906E - Switch, Configuration Manual

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Setting Other LLDP Parameters
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 LLDP frames 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
follows:
TTL = Min (65535, (TTL multiplier × LLDPDU transmit interval))
As the expression shows, the TTL can be up to 65535 seconds. TTLs greater than it will be rounded
down to 65535 seconds.
Follow these steps to change the TTL multiplier:
To do… Use the command… Remarks
Enter system view system-view —
Set the TTL multiplier lldp hold-multiplier value
Optional
4 by default.
Set the LLDPDU transmit
interval
lldp timer tx-interval interval
Optional
30 seconds by default
Set LLDPDU transmit delay lldp timer tx-delay delay
Optional
2 seconds by default
Set the number of LLDP frames
sent each time fast LLDPDU
transmission is triggered.
lldp fast-count count
Optional
3 by default
z
The TTL can be up to 65535 seconds. TTLs greater than it will be rounded down to 65535 seconds.
z
LLDPDU transmit delay must be less than the TTL to ensure that the LLDP neighbors can receive
LLDP frames to update information about the device you are configuring before it is aged out.
Setting an Encapsulation Format for LLDPDUs
LLDPDUs can be encapsulated in Ethernet II or SNAP frames.
z
With Ethernet II encapsulation configured, an LLDP port sends LLDPDUs in Ethernet II frames and
processes an incoming LLDP frame only when it is Ethernet II encapsulated.
z
With SNAP encapsulation configured, an LLDP port sends LLDPDUs in SNAP frames and
processes an incoming LLDP frame only when it is SNAP encapsulated.
By default, LLDPDUs are encapsulated in Ethernet II frames. If the neighbor devices encapsulate
LLDPDUs in SNAP frames, configure the encapsulation format for LLDPDUs as SNAP to guarantee
normal communication with the neighbors.
Follow these steps to set the encapsulation format for LLDPDUs to SNAP: