H3C SOHO IE4300, Command Reference Manual

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1
Loop detection commands
display loopback-detection
Use
display loopback-detection
to display the loop detection configuration and status.
Syntax
display loopback-detection
Views
Any view
Predefined user roles
network-admin
network-operator
Usage guidelines
In the command output, a port shut down by loop detection stays in looped state until it comes up.
Example
# Display the loop detection configuration and status.
<Sysname> display loopback-detection
Loop detection is enabled.
Loop detection interval is 30 second(s).
Loop is detected on following interfaces:
Interface Action mode VLANs
GigabitEthernet1/0/3 None 10
Table 1 Command output
Field Description
Action mode
Loop protection action:
•
Block —When a loop is detected on a port, the device performs the
following operations:

Generates a log.

Disables the port from learning MAC addresses.

Blocks the port.
•
None —When a loop is detected on a port, the device generates a log but
performs no action on the port.
•
No-learning —When a loop is detected on a port, the device generates a
log and disables the port from learning MAC addresses.
•
Shutdown —When a loop is detected on a port, the device performs the
following operations:

Generates a log.

Shuts down the port to disable the port from receiving or sending
frames. The device automatically sets the port to the forwarding state
after a time interval. Set the time interval by using the
shutdown-interval command (see Fundamentals Command
Reference ).
VLANs VLANs to which the interface belongs and where loops are detected.