PLANET XGS3-24040 - Manual (Page 125)

XGS3 Command Guide
6-125
Chapter 6 Commands for Port Loopback
Detection Function
6.1 loopback-detection control
Command:
loopback-detection control {shutdown |block| learning}
no loopback-detection control
Function:
Enable the function of loopback detection control on a port, the no operation of this command will disable the
function.
Parameters:
shutdown set the control method as shutdown, which means to close down the port if a port loopback is found.
block set the control method as block, which means to block a port by allowing bpdu and loopback detection
messages only if a port loopback is found.
learning disable the control method of learning MAC addresses on the port, not forwarding traffic and delete the
MAC address of the port.
Default:
Disable the function of loopback diction control.
Command Mode:
Port Mode.
Usage Guide:
If there is any loopback, the port will not recovery the state of be controlled after enabling control operation on the
port. If the overtime is configured, the ports will recovery normal state when the overtime is time-out. If the control
method is block, the corresponding relationship between instance and vlan id should be set manually by users, it
should be noticed when be used.
Example:
Enable the function of loopback detection control under port1/2 mode.
Switch(config)#interface ethernet 1/2
Switch(Config-If-Ethernet1/2)#loopback-detection control shutdown
Switch(Config-If-Ethernet1/2)#no loopback-detection control
6.2 loopback-detection specified-vlan
Command:
loopback-detection specified-vlan <vlan-list>
no loopback-detection specified-vlan [<vlan-list>]
Function:
Enable the function of loopback detection on the port and specify the VLAN to be checked; the no operation of this
command will disable the function of detecting loopbacks through this port or the specified VLAN.
Parameters:
<vlan-list> the list of VLANs allowed passing through the port. Given the situation of a trunk port, the specified
VLANs can be checked. So this command is used to set the vlan list to be checked.