CloudEngine 8800, 7800, 6800, and 5800 V200R019C10 Configuration Guide - Ethernet Switching

This document describes the configuration of Ethernet services, including configuring MAC address table, link aggregation, M-LAG, VLAN, QinQ, VLAN mapping, GVRP, STP/RSTP, MSTP, VBST, ERPS (G.8032), LBDT, and Layer 2 protocol transparent transmission.

Example for Configuring Loopback Detection

Example for Configuring Loopback Detection

Networking Requirements

As shown in Figure 13-3, if there is a loop on the network connected to the 10GE1/0/1 interface, broadcast storms will occur on the Switch or even the entire network.

To detect loops on the network connected to the switch and disabled downlink interfaces to reduce impacts on the switch and other networks, enable loopback detection on the Switch.

Figure 13-3 Loopback detection network diagram

Configuration Roadmap

The configuration roadmap is as follows:

  1. Enable loopback detection on the interface to detect loops on downlink networks.
  2. Specify the VLAN ID for loopback detection packets.
  3. Set loopback detection parameters to enable the interface automatic recovery.

Procedure

  1. Enable loopback detection on the interface.

    <HUAWEI> system-view
    [~HUAWEI] sysname Switch
    [*HUAWEI] commit
    [~Switch] interface 10ge 1/0/1
    [~Switch-10GE1/0/1] loopback-detect enable
    [*Switch-10GE1/0/1] commit
    [~Switch-10GE1/0/1] quit

  2. Specify the VLAN ID for loopback detection packets.

    [~Switch] vlan 100
    [*Switch-vlan100] quit
    [*Switch] interface 10ge 1/0/1
    [*Switch-10GE1/0/1] port link-type trunk
    [*Switch-10GE1/0/1] port trunk allow-pass vlan 100
    [*Switch-10GE1/0/1] loopback-detect vlan 100
    [*Switch-10GE1/0/1] commit
    [~Switch-10GE1/0/1] quit

  3. Set loopback detection parameters.

    # Configure the action the interface when a loopback is detected.

    [~Switch] loopback-detect action error-down
    [*Switch] commit

    # Set the interval between sending loopback detection packets.

    [~Switch] loopback-detect transmit interval 10
    [*Switch] commit

  4. Check the configuration.

    Run the display loopback-detect command to check the configuration.

    [~Switch] display loopback-detect 
    ------------------------------------------------------------                                                                        
     Loopback-detect transmit interval: 10s                                                                                             
    ------------------------------------------------------------                                                                        
    ------------------------------------------------------------                                                                        
    Interface                Action                   Status                                                                            
    ------------------------------------------------------------                                                                        
    10GE1/0/1                Error-Down               ErrorDown

Configuration Files

Configuration file of the Switch

#
sysname Switch
#
loopback-detect transmit interval 10
loopback-detect action error-down
#
vlan batch 100
#
interface 10GE1/0/1
 port link-type trunk
 port trunk allow-pass vlan 100
 loopback-detect enable
 loopback-detect vlan 100
#
return