Loopback - H3C S5120-EI Series Command Reference Manual

By default, link up suppression is disabled. Ethernet ports report link up events to the upper layers without
delay.
NOTE:
The link-delay mode up command and the link-delay command supersedes each other, and whichever
•
is configured last takes effect.
Link up suppression setting does not take effect on administratively up events. When you bring up the
•
port with the undo shutdown command, the port reports the event without delay.
• H3C does not recommend that you use this command on ports that are disabled with RRPP, MSTP, or
Smart Link.
Examples
# Enable link up suppression on port GigabitEthernet 1/0/1, setting the suppression interval to 10
seconds.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
[Sysname-GigabitEthernet1/0/1] link-delay 10 mode up

loopback

Syntax
loopback { external | internal }
View
Ethernet interface view
Default level
2: System level
Parameters
external: Enables external loopback testing to test all on-chip functions related to Ethernet ports.
internal: Enables internal loopback testing to test hardware of Ethernet ports.
Description
Use the loopback command to perform loopback testing.
NOTE:
You can perform neither internal nor external loopback testing on an administratively down (ADM
•
DOWN) port. On a physically down (DOWN) port, you can perform only internal loopback testing.
• During loopback testing, the speed, duplex, mdi, and shutdown commands are not available. In
addition, the port is operating in full duplex mode, regardless of its duplex configuration. After
loopback testing is disabled, the duplex configuration of the port is restored.
Loopback testing is a one-time operation, and is not recorded in the configuration file.
•
Examples
# Enable internal loopback testing on port GigabitEthernet 1/0/1.
<Sysname> system-view
[Sysname] interface gigabitethernet 1/0/1
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