3com S7906E Manuel De Montage

 

1-2 

z 

The port is not configured with MSTP, the member port of an isolation group, 802.1X, MAC address 

authentication, port security mode, or IP source guard. Additionally, the member port of a service 

loopback group cannot be configured with any of the above-mentioned configurations.  

z 

The port belongs to VLAN 1.  

z 

The port is not a member of any aggregation group or service loopback group.  

A member port in a service loopback group can be in one of the following two states: 

z 

Selected: a selected port can forward user traffic.  

z 

Unselected: an unselected port cannot forward user traffic.  

The system sets the state of each port in a service loopback group to selected or unselected as follows: 

z 

Select the full-duplex port with the highest rate as the reference port. If two ports with the same 

duplex mode/speed pair are present, the one with the lower port number wins out. 

z 

Consider the ports the same as the reference port in rate, duplex mode, and hardware restrictions 

as candidate selected ports, and set the rest ports to unselected state.  

z 

The number of selected ports is limited in a service loopback group. If the number of candidate 

ports exceeds the limit, those with smaller port IDs are set to selected state and the others are set 

to unselected state.  

 

The system follows the preemption principle when setting port state in a service loopback group. If the 

port you are assigning to a service loopback group can be set to selected state, the system will do that, 

even if this can cause an existing selected port to transit to unselected.  

 

Follow these steps to configure a service loopback group: 

Enter system view 

— 

Create a service loopback 
group 

service-loopback group number 
type { multicast-tunnel | tunnel } * 

Required 

Enter Layer-2 Ethernet 
interface view 

interface interface-type 
interface-number 

Assign the Ethernet 
interface to the specified 
service loopback group 

port service-loopback group 
number 

Required 

By default, a port does not 
belong to any service 
loopback group 

Repeat the two steps to 
assign multiple Ethernet 
interfaces to the service 
loopback group.