Loopback-Detection (Interface) - D-Link DGS-6600-48TS Manual

DGS-6604 m

loopback-detection (interface)

loopback-detection
no loopback-detection
Syntax
Default
Command Mode
Usage Guideline
Prompt Message
Prompt message at screen
Cannot enable LBD on the port as it
is STP enabled.
Example
Switch(config)# interface eth3.1
Switch(config-if)# loopback-detection
Switch(config-if)#
CLI Reference Guide
Use the command to enable interface loopback detection function. Use the no
form to disable the function.
None
Disabled
Interface mode
The command is available for port and port channel interface configuration.
When a port enables the loopback-detection function, and switch is in forwarding
state, will periodically sends out CTP packets with the SA field set to device's
MAC, DA field set to CF-00-00-00-00-00. Type is "90-00". If the port is an
untagged member of a VLAN, this port will send out the untagged CTP packet. If
the port is only tagged member of VLAN, then this port will send out the tagged
packet with one of the VLAN ID to which this port belonged.
When the switch detects that a CTP packet sent out by the port has been looped
back to the packet originating port, it will put this port into error disabled state or
block the traffic which belong to this VLAN according to the detection mode user
configured.
There are two kinds of recovery mechanisms provide, user can bring it out of this
state by entering the "errdisable recovery cause loopback-detection" global
configuration command. Alternatively, the user can manually re-enable the port
by entering the "shutdown" then "no shutdown" command in interface-
configuration mode.
The LBD will work only when both the global setting and port setting are enabled.
This example shows how to enable loopback detection function on port3.1
Description
STP and LBD should be mutual exclusive on the same port.
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