Managing Physical Interfaces
Configuration Examples
User Guide
107
Port LAG Forward-List
---- --- ------------
Gi1/0/1 N/A Gi1/0/4
Gi1/0/2 N/A Gi1/0/1-28,Po1-14
Gi1/0/3 N/A Gi1/0/1-28,Po1-14
Gi1/0/4 N/A Gi1/0/1
...
5.2 Example for Loopback Detection
5.2.1 Network Requirements
As shown below, Switch A is a convergence-layer switch connecting to 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 5-5
Network Topology
Switch A
Management Host
Access-layer Switches
Gi1/0/1
Gi1/0/2
Loop
Gi1/0/3
5.2.2 Configuration Scheme
Enable loopback detection on ports 1/0/1-3 and configure SNMP to receive the trap
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 TL-SG2210P, the following sections provide configuration procedure in
two ways: using the GUI and using the CLI.
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