Lenovo Flex System Fabric CN4093, Application Manual

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CN4093 Application Guide for N/OS 8.4
LLDP Overview
Link Layer Discovery Protocol (LLDP) is an IEEE 802.1AB ‐ 2005 standard for
discovering and managing network devices. LLDP uses Layer 2 (the data link
layer), and allows network management applications to extend their awareness of
the network by discovering devices that are direct neighbors of already known
devices.
With LLDP, the CN4093 can advertise the presence of its ports, their major
capabilities, and their current status to other LLDP stations in the same LAN.
LLDP transmissions occur on ports at regular intervals or whenever there is a
relevant change to their status. The switch can also receive LLDP information
advertised from adjacent LLDP ‐ capable network devices.
In addition to discovery of network resources, and notification of network changes,
LLDP can help administrators quickly recognize a variety of common network
configuration problems, such as unintended VLAN exclusions or mis ‐ matched
port aggregation membership.
The LLDP transmit function and receive function can be independently configured
on a per ‐ port basis. The administrator can allow any given port to transmit only,
receive only, or both transmit and receive LLDP information.
The LLDP information to be distributed by the CN4093 ports, and that which has
been collected from other LLDP stations, is stored in the switch’s Management
Information Base (MIB). Network Management Systems (NMS) can use Simple
Network Management Protocol (SNMP) to access this MIB information.
LLDP ‐ related MIB information is read ‐ only.
Changes, either to the local switch LLDP information or to the remotely received
LLDP information, are flagged within the MIB for convenient tracking by
SNMP ‐ based management systems.
For LLDP to provide expected benefits, all network devices that support LLDP
should be consistent in their LLDP configuration.
LLDP - Stacking Mode
In stacking mode, LLDP can be configured only on the ports that are not used to
create the stack. The LLDP configuration menus on the stacking ports are disabled.
When configuring LLDP on a port, use the correct port syntax. See example of port
syntax on page 241 .