Command Manual (For Soliton) – Port Basic Configuration
H3C S3100 Series Ethernet Switches
Chapter 1 Port Basic Configuration
Commands
1-26
Parameter
None
Description
Use the
loopback-detection enable
command to enable the loopback detection
function on the current port to detect whether an external loopback occurs on the port.
Use the
undo loopback-detection enable
command to disable the loopback
detection function on the port.
1)
If a loop is found on an access port, the system will set the port to the
block
state
(ports in this state cannot forward data packets), send log messages to the
terminal, and remove the corresponding MAC forwarding entry.
z
If you have enabled the loopback port auto-shutdown function (with the
loopback-detection shutdown enable
command) on the access port, the system
will shut down the port, and send log messages to the terminal. After the loop is
removed, you need to use the
undo shutdown
command to bring up the port.
z
If you have not enabled the loopback port auto-shutdown function on the access
port, the port will automatically resume the normal forwarding state after the loop is
removed.
2)
If a loop is found on a trunk or hybrid port, the system sends log messages to the
terminal. If you have additionally enabled the loopback port control function or the
loopback port auto-shutdown function, the system will deal with the port
accordingly:
z
If the loopback port control function is enabled on the port (with the
loopback-detection control enable
command), the system will set the port to the
block
state (ports in this state cannot forward data packets), send log messages
to the terminal, and remove the corresponding MAC forwarding entry. After the
loop is removed, the port will automatically resume the normal forwarding state.
z
If the loopback port auto-shutdown function is enabled on the port (with the
loopback-detection shutdown enable
command), the system will shut down the
port and send log messages to the terminal. After the loop is removed, you need to
use the
undo shutdown
command to bring up the port.
Note:
The loopback detection function on a specific port can take effect only after you enable
the loopback detection function globally (in system view) and on the port (in the
specified port view).
