Management and Configuration Guide K/KA/KB.15.15

Enable or disable LLDP on the switch
In the default configuration, LLDP is globally enabled on the switch. To prevent transmission or
receipt of LLDP traffic, you can disable LLDP operation.
Enabling or disabling LLDP-MED
In the default configuration for the switches, LLDP-MED is enabled by default which requires that
LLDP is also enabled.
Changing the frequency of LLDP packet transmissions to neighbor devices
On a global basis, you can increase or decrease the frequency of outbound LLDP advertisements
(see syntax (page 221).)
Changing the Time-To-Live for LLDP packets sent to neighbors
On a global basis, you can increase or decrease the time that the information in an LLDP packet
outbound from the switch will be maintained in a neighbor LLDP device (see syntax (page 221).)
Transmit and receive mode
With LLDP enabled, the switch periodically transmits an LLDP advertisement (packet) out each active
port enabled for outbound LLDP transmissions and receives LLDP advertisements on each active
port enabled to receive LLDP traffic (Section (page 223).) Per-port configuration options include
four modes:
• Transmit and receive ( tx_rx): This is the default setting on all ports. It enables a given port
to both transmit and receive LLDP packets and to store the data from received (inbound) LLDP
packets in the switch's MIB.
• Transmit only ( txonly): This setting enables a port to transmit LLDP packets that can be read
by LLDP neighbors. However, the port drops inbound LLDP packets from LLDP neighbors without
reading them. This prevents the switch from learning about LLDP neighbors on that port.
• Receive only ( rxonly): This setting enables a port to receive and read LLDP packets from
LLDP neighbors and to store the packet data in the switch's MIB. However, the port does not
transmit outbound LLDP packets. This prevents LLDP neighbors from learning about the switch
through that port.
• Disable ( disable): This setting disables LLDP packet transmissions and reception on a port.
In this state, the switch does not use the port for either learning about LLDP neighbors or
informing LLDP neighbors of its presence.
SNMP notification
You can enable the switch to send a notification to any configured SNMP trap receiver(s) when
the switch detects a remote LLDP data change on an LLDP-enabled port (SNMP notification support
(page 256).)
Per-port (outbound) data options
The following table lists the information the switch can include in the per-port, outbound LLDP
packets it generates. In the default configuration, all outbound LLDP packets include this information
in the TLVs transmitted to neighbor devices. However, you can configure LLDP advertisements on
a per-port basis to omit some of this information (Section (page 223).)
Table 19 Data available for basic LLDP advertisements
DescriptionDefaultConfiguration optionsData type
The length of time an LLDP
neighbor retains the
120 Seconds
1
.Time-to-Live
LLDP 253