- Table of Contents
-
- H3C Low-End Ethernet Switches Configuration Guide(V1.01)
- 01-Login Configuration Guide
- 02-VLAN Configuration Guide
- 03-IP Address Configuration Guide
- 04-Voice VLAN Configuration Guide
- 05-GVRP Configuration Guide
- 06-Ethernet Interface Basic Configuration Guide
- 07-Link Aggregation Configuration Guide
- 08-Port Isolation Configuration Guide
- 09-Port Security Configuration Guide
- 10-Port Binding Configuration Guide
- 11-MAC Address Table Management Configuration Guide
- 12-DLDP Configuration Guide
- 13-Auto Detect Configuration Guide
- 14-MSTP Configuration Guide
- 15-Routing Configuration Guide
- 16-Multicast Configuration Guide
- 17-802.1x Configuration Guide
- 18-AAA Configuration Guide
- 19-MAC Authentication Configuration Guide
- 20-VRRP Configuration Guide
- 21-ARP Configuration Guide
- 22-DHCP Configuration Guide
- 23-ACL Configuration Guide
- 24-QoS-QoS Profile Configuration Guide
- 25-Web Cache Redirection Configuration Guide
- 26-Mirroring Configuration Guide
- 27-IRF Configuration Guide
- 28-Cluster Configuration Guide
- 29-PoE-PoE Profile Configuration Guide
- 30-UDP Helper Configuration Guide
- 31-SNMP-RMON Configuration Guide
- 32-NTP Configuration Guide
- 33-SSH Configuration Guide
- 34-FTP and TFTP Configuration Guide
- 35-Information Center Configuration Guide
- 36-VLAN-VPN Configuration Guide
- 37-HWPing Configuration Guide
- 38-DNS Configuration Guide
- 39-Access Management Configuration Guide
- 40-Web Authentication Configuration Guide
- 41-IPv6 Management Configuration Guide
- 42-Smart link - Monitor Link Configuration Guide
- 43-VLAN Mapping Configuration Guide
- Related Documents
-
Title | Size | Download |
---|---|---|
12-DLDP Configuration Guide | 36.39 KB |
Configuring DLDP
Sometimes, unidirectional links may appear in networks. On a unidirectional link, one end can receive packets from the other end but the other end cannot.
Unidirectional links can be caused by fiber cross-connection or fiber cut (including single-fiber cut and lack of a fiber connection).
They can cause problems such as spanning tree topology loops.
You can use the Device Link Detection Protocol (DLDP) to monitor the link status of optical fiber cables and copper twisted pairs such as super category 5 twisted pairs. Once detecting a unidirectional link, DLDP shuts down the port or ask you to do so depending on your configuration.
Network Diagram
Figure 1-1 Network diagram for DLDP configuration
Networking and Configuration Requirements
l Switch A and Switch B are connected through two pairs of fibers. The connecting ports are operating in mandatory full duplex mode at 1000 Mbps. Both of the switches support DLDP.
l Configure DLDP to automatically disconnect the detected unidirectional link.
l After the fibers are connected correctly, the port shut down by DLDP restores automatically.
Applicable Product Matrix
Product series |
Software version |
Hardware version |
S5600 series Ethernet switches |
Release 1510, Release 1602 |
All versions |
S5100-SI/EI series Ethernet switches |
Release 2200, Release 2201 |
All versions |
S3600-SI/EI series Ethernet switches |
Release 1510, Release 1602 |
All versions |
S3100-EI series Ethernet switches |
Release 2104, Release 2107 |
All versions |
S3100-52P |
Release 1500, Release 1602 |
S3100-52P |
Configuration Procedure
l Configure Switch A
# Configure the ports to work in mandatory full duplex mode at 1000 Mbps.
<SwitchA> system-view
[SwitchA] interface GigabitEthernet 1/1/3
[SwitchA-GigabitEthernet1/1/3] duplex full
[SwitchA-GigabitEthernet1/1/3] speed 1000
[SwitchA-GigabitEthernet1/1/3] quit
[SwitchA] interface GigabitEthernet 1/1/4
[SwitchA-GigabitEthernet1/1/4] duplex full
[SwitchA-GigabitEthernet1/1/4] speed 1000
[SwitchA-GigabitEthernet1/1/4] quit
# Enable DLDP globally.
[SwitchA] dldp enable
# Set the interval for sending DLDP packets to 15 seconds.
[SwitchA] dldp interval 15
# Configure DLDP to operate in enhanced mode.
[SwitchA] dldp work-mode enhance
# Configure DLDP to shut down a port automatically once a unidirectional link is detected on it.
[SwitchA] dldp unidirectional-shutdown auto
# Set the DelayDown timer to five seconds.
[SwitchA] dldp delaydown-timer 5
# Display the DLDP state.
[SwitchA] display dldp 1
# Restore the ports brought down by DLDP.
[SwitchA] dldp reset
l Configure Switch B
The configuration on Switch B is the same as that on Switch A.
Complete Configuration
l Configuration on Switch A
#
dldp interval 15
dldp work-mode enhance
dldp delaydown-timer 5
#
interface Gigabitethernet 1/1/3
duplex full
speed 1000
dldp enable
#
interface Gigabitethernet 1/1/4
duplex full
speed 1000
dldp enable
l Configuration on Switch B
The configuration on Switch B is the same as that on Switch A.
Precautions
1) When enabling DLDP on two connected devices, make sure that they are using the same software version. Otherwise, DLDP may malfunction.
2) When optical fibers are cross-connected, two or three ports are in the disable state, and the remaining ports are in the inactive state.
3) DLDP in the enhanced mode can identify unidirectional links caused by fiber cross-connection or fiber cut.
4) DLDP in the normal mode can identify only unidirectional links caused by fiber cross-connection.