Extreme Networks ExtremeWare XOS 11.3, Руководство пользователя

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Link Layer Discovery Protocol
ExtremeWare XOS 11.3 Concepts Guide
152
Mandatory TLVs
This section discusses the following mandatory TLVs, which are automatically enabled once you enable
LLDP on a port:
●
Chassis ID TLV on page 152
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Port ID TLV on page 152
●
TTL TLV on page 152
●
End-of-LLDPDU TLV on page 152
Chassis ID TLV
This mandatory TLV is sent by default once you enable LLDP on the port. It is not configurable.
The ExtremeWare XOS software uses the system’s MAC address to uniquely identify the device. EDP
also uses this to identify the device.
Port ID TLV
This mandatory TLV is sent by default once you enable LLDP on the port; you cannot configure this
TLV. The port ID TLV is used to uniquely identify the port within the device.
The software uses the ifName object for this TLV, so it is the port number on stand-alone switches and
the combination of slot and port number on modular switches.
TTL TLV
The TTL TLV is mandatory, sent by default once LLDP is enabled, and nonconfigurable. This TLV
indicates how long the record should be maintained in the LLDP database. The default value is 120
seconds (or 2 minutes).
A value of 0 in the TTL TLV means the client is shutting down and that record should be deleted from
the database. When you disable an LLDP port, the triggered update LLDPU from that port contains a
TTL TLV of zero.
The TTL TLV is mandatory and is sent by default once LLDP is enabled. Although, technically, you do
not configure the TTL TLV, you
can configure the transmit hold value, which is used to calculate the
TTL TLV. (See “Configuring LLDP Timers” on page 157 for more information on transmit hold value
and TTL.)
End-of-LLDPDU TLV
The end-of-LLDPDU TLV marks the end of the data. The system automatically adds this TLV to the
LLDPDU once you enable LLDP.
Optional TLVs
All the optional TLVs are configurable using the CLI and/or SNMP.