Configuration Guide
102
Managing Physical Interfaces
Configuration Examples
7.3 Example for Loopback Detection
7.3.1 Network Requirements
As shown below, Switch A is a convergence-layer switch connecting several access-
layer switches. Loops can be easily caused in case of misoperation on the access-
layer switches. If there is a loop on an access-layer switch, broadcast storms will occur
on Switch A or even in the entire network, creating excessive traffic and degrading the
network performance.
To reduce the impacts of broadcast storms, users need to detect loops in the network via
Switch A and timely block the port on which a loop is detected.
Figure 7-8
Network Topology
Switch A
Management Host
Access-layer Switches
Gi1/0/1
Gi1/0/2
Loop
Gi1/0/3
7.3.2 Configuration Scheme
Enable loopback detection on ports 1/0/1-3 and configure SNMP to receive the
notifications. For detailed instructions about SNMP, refer to
Here we introduce how to configure loopback detection and monitor the detection result
on the management interface of the switch.
Demonstrated with T1600G-52TS, the following sections provide configuration procedure
in two ways: using the GUI and using the CLI.
7.3.3 Using the GUI
1) Choose the menu
Switching > Port > Loopback Detection
to load the configuration
page.
2) In the
Global Config
section, enable loopback detection and web refresh globally. Keep
the default parameters and click
Apply
.
