Starting LB

Perform loopback for the Ethernet service without interrupting the service to check the connectivity of the service and thus to locate and rectify the fault. The loopback (LB) can be used to test the state of any node link from the source to the maintenance domain. As the sink MP can be the MIP, the loopback can be used to locate the faults. Compared with the continuity test, the loopback test is not a continuous test. Thus, you need start the test manually each time.

Navigation Path

Starting the LB test for the Ethernet service OAM management, E-Line service, E-LAN service service requires information in this interface.

For RTN NEs, in the NE Explorer, right-click the NE and choose Configuration > Ethernet OAM Management > Ethernet Service OAM Management. Then, choose OAM > Start LB.
For RTN NEs, in the NE Explorer, right-click the NE and choose Configuration > Ethernet Service Management > E-Line Service. Then, click the MEP Point tab and choose OAM > Start LB.
For RTN NEs, in the NE Explorer, right-click the NE and choose Configuration > Ethernet Service Management > E-LAN Service. Then, click the MEP Point tab and choose OAM > Start LB.

Buttons

Button	Description
Start Test	Start the LB test.
Stop Test	Stop the LB test.

Parameters

**Table 1** Descriptions of the parameters for Starting LB
Field	Value	Description
Maintenance Domain Name	8 bytes	Display the name of the maintenance domain.
Maintenance Association Name	8 bytes	Display the name of the maintenance association.
Source Maintenance Point ID	Example: 5	Set the source maintenance point for the LB test.
Destination Maintenance Point MAC Address	Example: 1A-2B-3C-4D-5E-6F	Set the MAC address of the sink maintenance point.
Destination Maintenance Point ID	Example: 5	Set the sink maintenance point ID.
Transmitted Packet Count	Example: 3	Set the count of packets transmitted each time.
Transmitted Packet Length	Example: 80 (default: 64)	Set the length of packets transmitted each time.
Transmitted Packet Priority	0-7 (default: 7)	Set the priority for transmitting packets.
Detection Result	Character string	Display the detection result.