Configuring Loopback Testing On An Ethernet Interface - H3C S3600V2 SERIES Layer 2-Lan Switching Configuration Manual

the physical link is still down when the timer expires, the interface reports the link-down event to the upper
layers.
Link-up event suppression enables an interface to suppress link-up events and start a delay timer each
time the physical link goes up. During this delay, the interface does not report the link-up event, and the
display interface brief or display interface command displays the interface state as DOWN. If the
physical link is still up when the timer expires, the interface reports the link-up event to the upper layers.
Configuring link-down event suppression
To enable an Ethernet interface to suppress link-down events:
Step
1. Enter system view.
2. Enter Ethernet interface
view.
3. Set a link-down event
suppression interval.
Configuring link-up event suppression
To configure link-up event suppression on an Ethernet interface:
Step
1. Enter system view.
2. Enter Ethernet interface
view.
3. Set a link-up event
suppression interval.
NOTE:
The link-delay mode up command and the link-delay command supersedes each other, and whichever is
configured last takes effect.

Configuring loopback testing on an Ethernet interface

If an Ethernet interface does not work correctly, you can enable loopback testing on it to identify the
problem. Loopback testing has the following types:
Internal loopback testing—Tests all on-chip functions related to Ethernet interfaces.
•
External loopback testing—Tests hardware of Ethernet interfaces. To perform external loopback
•
testing on an Ethernet interface, connect a loopback plug to the Ethernet interface. The switch sends
test packets out of the interface, which are expected to loop over the plug and back to the interface.
If the interface fails to receive any test packet, the hardware of the interface is faulty.
An Ethernet interface in a loopback test does not forward data traffic.
Configuration restrictions and guidelines
• On an interface administratively shut down, you can perform neither internal nor external loopback
testing.
Command
system-view
interface interface-type
interface-number
link-delay delay-time
Command
system-view
interface interface-type
interface-number
link-delay delay-time mode up
5
Remarks
N/A
N/A
Link-down event suppression is disabled by
default.
Remarks
N/A
N/A
Link-up event suppression is disabled by
default.