User manual

C HAPTER 4 | Configuring the Switch
Link Layer Discovery Protocol
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◆ Mode – Enables LLDP message transmit and receive modes for LLDP
Protocol Data Units. (Options: Disabled, Enabled - TxRx, Rx only,
Tx only; Default: Disabled)
◆ CDP Aware – Enables decoding of Cisco Discovery Protocol frames.
(Default: Disabled)
If enabled, CDP TLVs that can be mapped into a corresponding field in
the LLDP neighbors table are decoded, all others are discarded. CDP
TLVs are mapped into LLDP neighbors table as shown below:
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CDP TLV “Device ID” is mapped into the LLDP “Chassis ID” field.
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CDP TLV “Address” is mapped into the LLDP “Management Address”
field. The CDP address TLV can contain multiple addresses, but only
the first address is shown in the LLDP neighbors table.
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CDP TLV “Port ID” is mapped into the LLDP “Port ID” field.
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CDP TLV “Version and Platform” is mapped into the LLDP “System
Description” field.
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Both the CDP and LLDP support “system capabilities,” but the CDP
capabilities cover capabilities that are not part of LLDP. These
capabilities are shown as “others” in the LLDP neighbors table.
If all ports have CDP awareness disabled, the switch forwards CDP
frames received from neighbor devices. If at least one port has CDP
awareness enabled, all CDP frames are terminated by the switch.
When CDP awareness for a port is disabled, the CDP information is not
removed immediately, but will be removed when the hold time is
exceeded.
Optional TLVs - Configures the information included in the TLV field of
advertised messages.
◆ Port Descr – The port description is taken from the ifDescr object in
RFC 2863, which includes information about the manufacturer, the
product name, and the version of the interface hardware/software.
◆ Sys Name – The system name is taken from the sysName object in
RFC 3418, which contains the system's administratively assigned
name. To configure the system name, see page 45.
◆ Sys Descr – The system description is taken from the sysDescr object
in RFC 3418, which includes the full name and version identification of
the system's hardware type, software operating system, and
networking software.
◆ Sys Capa – The system capabilities identifies the primary function(s)
of the system and whether or not these primary functions are enabled.
The information advertised by this TLV is described in IEEE 802.1AB.
◆ Mgmt Addr – The management address protocol packet includes the
IPv4 address of the switch. If no management address is available, the
address should be the MAC address for the CPU or for the port sending
this advertisement.