Table of Contents

1 LLDP Configuration Guide· 1-1

LLDP· 1-1

Configuring LLDP· 1-1

Network Diagram·· 1-1

Networking and Configuration Requirements· 1-1

Applicable Product Matrix· 1-1

Configuration Procedure· 1-2

Complete Configuration· 1-4

Configuration Guidelines· 1-4

CDP-Compatible LLDP Configuration Example· 1-5

Network diagram·· 1-5

Network requirements· 1-5

Applicable Product Matrix· 1-5

Configuration Procedure· 1-5

Complete Configuration· 1-6

Configuration Guidelines· 1-7

 

LLDP

The Link Layer Discovery Protocol (LLDP) operates on the data link layer. It stores and maintains information about the local device and the devices directly connected to it for network administrators to manage networks through NMS (network management systems). In LLDP, device information is encapsulated in LLDPDUs in the form of TLV (meaning type, length, and value) triplets and is exchanged between directly connected devices. Information in LLDPDUs received is stored in standard MIB (management information base).

Configuring LLDP

Network Diagram

Figure 1-1 Network diagram for LLDP configuration

 

Networking and Configuration Requirements

l          As shown in Figure 1-1, connect NMS to Switch A over the Ethernet; and connect Switch A to the MED device and Switch B through GigabitEthernet 1/0/1 and GigabitEthernet 1/0/2 respectively.

l          Configure LLDP on the interfaces of Switch A and Switch B to allow NMS to monitor the link status of Switch A.

Applicable Product Matrix

Product series	Software version	Hardware version
S5500-EI series Ethernet switches	Release 2102	All versions
S7500E series Ethernet switches	Release 6100	All versions

 

Configuration Procedure

1)        Configure Switch A

# Enter system view:

<SwitchA> system-view

# Enable LLDP globally.

[SwitchA] lldp enable

# Enable LLDP on interfaces GigabitEthernet 1/0/1 and GigabitEthernet 1/0/2 respectively and set the LLDP work mode to rx.

[SwitchA] interface GigabitEthernet1/0/1

[SwitchA-GigabitEthernet1/0/1] lldp enable

[SwitchA-GigabitEthernet1/0/1] lldp admin-status rx

[SwitchA-GigabitEthernet1/0/1] quit

[SwitchA] interface GigabitEthernet1/0/2

[SwitchA-GigabitEthernet1/0/2] lldp enable

[SwitchA-GigabitEthernet1/0/2] lldp admin-status rx

[SwitchA-GigabitEthernet1/0/2] quit

2)        Configure Switch B

# Enter system view:

<SwitchB> system-view

# Enable LLDP globally.

[SwitchB] lldp enable

# Enable LLDP on interface GigabitEthernet 1/0/1 and set the LLDP work mode to tx.

[SwitchB] interface GigabitEthernet1/0/1

[SwitchB-GigabitEthernet1/0/1] lldp enable

[SwitchB-GigabitEthernet1/0/1] lldp admin-status tx

3)        Verify the configuration

# Display global and port-level LLDP status on Switch A.

<SwitchA> display lldp status

Global status of LLDP : Enable

The current number of neighbors : 2

Neighbor information last changed time : 0 days, 0 hours, 4 minutes, 40 seconds

Transmit interval               : 30s

Hold multiplier                 : 4

Reinit delay                    : 2s

Transmit delay                  : 2s

Trap interval                   : 5s

Fast start times                : 3

 

Port 0 [GigabitEthernet1/0/1] :

Port status of LLDP             : Enable

Admin status                    : Rx_Only

Trap flag                       : No

Roll time                       : 0s

 

Number of neighbors              : 1

Number of MED neighbors          : 1

Number of sent optional TLV      : 0

Number of received unknown TLV   : 0

 

Port 1 [GigabitEthernet1/0/2] :

Port status of LLDP             : Enable

Admin status                    : Rx_Only

Trap flag                       : No

Roll time                       : 0s

 

Number of neighbors              : 1

Number of MED neighbors          : 0

Number of sent optional TLV      : 0

Number of received unknown TLV   : 3

……(information for other ports omitted)

# By default, the telnet terminal monitor is disabled. To display the log information generated by LLDP status changes on NMS, enable the terminal monitor.

<SwitchA> terminal monitor

# Tear down the link between Switch A and Switch B, and enable the terminal monitor to display the following log information on Switch A (that on Switch B is similar):

%Nov 21 11:38:42:86 2007 H3C IFNET/4/LINK UPDOWN: GigabitEthernet1/0/2: link status is DOWN

%Nov 21 11:40:26:846 2007 H3C LLDP/2/AGEOUTREM:Port GigabitEthernet1/0/2 (IfIndex 9437201):Neighbor aged out, chassis ID: 000f-e272-8351, port ID: GigabitEthernet1/0/1.

# Display global and port-level LLDP status on Switch A.

<SwitchA> display lldp status

Global status of LLDP : Enable

The current number of neighbors : 1

Neighbor information last changed time : 0 days, 0 hours, 5 minutes, 20 seconds

Transmit interval               : 30s

Hold multiplier                 : 4

Reinit delay                    : 2s

Transmit delay                  : 2s

Trap interval                   : 5s

Fast start times                : 3

 

Port 0 [GigabitEthernet1/0/1] :

Port status of LLDP             : Enable

Admin status                    : Rx_Only

Trap flag                       : No

Roll time                       : 0s

 

Number of neighbors              : 1

Number of MED neighbors          : 1

Number of sent optional TLV      : 0

Number of received unknown TLV   : 5

 

Port 1 [GigabitEthernet1/0/2] :

Port status of LLDP             : Enable

Admin status                    : Rx_Only

Trap flag                       : No

Roll time                       : 0s

 

Number of neighbors              : 0

Number of MED neighbors          : 0

Number of sent optional TLV      : 0

Number of received unknown TLV   : 0

……(information for other ports omitted)

Complete Configuration

l          Configuration on Switch A

#

interface GigabitEthernet1/0/1

 lldp admin-status rx

#

interface GigabitEthernet1/0/2

 lldp admin-status rx

l          Configuration on Switch B

#

interface GigabitEthernet1/0/1

 lldp admin-status tx

Configuration Guidelines

To display the log information generated by neighbor status changes on the terminal monitor, make sure that the terminal monitor (through the terminal monitor command), log information switch (through the terminal logging command), and information center (through the info-center enable command) are enabled. The example in this document involves the terminal monitor configuration only, since the telnet terminal monitor of the S5500-EI is disabled while the log information switch and the information center are enabled by default. For details, refer to the Information Center module in the Operation Manual.

CDP-Compatible LLDP Configuration Example

Network diagram

Figure 1-2 Network diagram for LLDP compatible with CDP configuration

Network requirements

l          GigabitEthernet 2/0/1 and GigabitEthernet 2/0/2 of Switch A are each connected to a Cisco IP phone.

l          Configure voice VLAN 2 on Switch A. Enable CDP compatibility of LLDP on Switch A to allow the Cisco IP phones to automatically configure the voice VLAN, thus confining their voice traffic within the voice VLAN to be isolated from other types of traffic.

Applicable Product Matrix

Product series	Software version	Hardware version
S7500E series Ethernet switches	Release 6300	All versions

Configuration Procedure

1)         Configure the voice VLAN on Switch A

# Create VLAN 2.

<SwitchA> system-view

[SwitchA] vlan 2

[SwitchA-vlan2] quit

# Enable the voice VLAN feature globally and configure VLAN 2 as the voice VLAN.

[SwitchA] voice vlan 2 enable

# Enable the voice VLAN feature on GigabitEthernet 2/0/1 and GigabitEthernet 2/0/2.

[SwitchA] interface GigabitEthernet 2/0/1

[SwitchA-GigabitEthernet2/0/1] voice vlan enable

[SwitchA-GigabitEthernet2/0/1] quit

[SwitchA] interface GigabitEthernet 2/0/2

[SwitchA-GigabitEthernet2/0/2] voice vlan enable

[SwitchA-GigabitEthernet2/0/2] quit

2)         Configure CDP-compatible LLDP on Switch A.

# Enable LLDP globally.

[SwitchA] lldp enable

# Enable LLDP to be compatible with CDP globally.

[SwitchA] lldp compliance cdp

# Enable LLDP, configure LLDP to operate in TxRx mode, and configure CDP-compatible LLDP to operate in TxRx mode on GigabitEthernet 2/0/1 and GigabitEthernet 2/0/2.

[SwitchA] interface GigabitEthernet 2/0/1

[SwitchA-GigabitEthernet2/0/1] lldp enable

[SwitchA-GigabitEthernet2/0/1] lldp admin-status txrx

[SwitchA-GigabitEthernet2/0/1] lldp compliance admin-status cdp txrx

[SwitchA-GigabitEthernet2/0/1] quit

[SwitchA] interface GigabitEthernet 2/0/2

[SwitchA-GigabitEthernet2/0/2] lldp enable

[SwitchA-GigabitEthernet2/0/2] lldp admin-status txrx

[SwitchA-GigabitEthernet2/0/2] lldp compliance admin-status cdp txrx

[SwitchA-GigabitEthernet2/0/2] quit

3)         Verify the configuration

# Display the neighbor information on Switch A.

[SwitchA] display lldp neighbor-information

CDP neighbor-information of port 97[GigabitEthernet2/0/1]:

  CDP neighbor index : 1

  Chassis ID         : SEP00141CBCDBFE

  Port ID            : Port 1

  Sofrware version   : P0030301MFG2

  Platform           : Cisco IP Phone 7960

  Duplex             : Full

 

CDP neighbor-information of port 98[GigabitEthernet2/0/2]:

  CDP neighbor index : 2

  Chassis ID         : SEP00141CBCDBFF

  Port ID            : Port 1

  Sofrware version   : P0030301MFG2

  Platform           : Cisco IP Phone 7960

  Duplex             : Full

Complete Configuration

#

 voice vlan 2 enable

#

lldp compliance cdp

#  

vlan 2

#

interface GigabitEthernet2/0/1

 port access vlan 2

 undo voice vlan mode auto

 voice vlan enable

 lldp compliance admin-status cdp txrx

#

interface GigabitEthernet2/0/2

 port access vlan 2

 undo voice vlan mode auto

 voice vlan enable

 lldp compliance admin-status cdp txrx

#        

Configuration Guidelines

l          For detailed information about voice VLAN, refer to VLAN Configuration Guide.

l          LLDP is enabled on the port connected to an IP phone and is configured to operate in TxRx mode on the port.

l          As the maximum TTL allowed by CDP is 255 seconds, your TTL configuration, that is, the product of the TTL multiplier and the LLDPDU sending interval, must be less than 255 seconds for CDP-compatible LLDP to work properly with Cisco IP phones.