Huawei OptiX OSN 2500 Supporting Tasks of Software Loopback

Outloop
The SDH optical interface board, PDH electrical interface board, Ethernet interface board like Huawei EGS4  and ATM board all support outloop.

Inloop
The SDH optical interface board like Huawei SLD64, PDH electrical interface board, Ethernet interface board and ATM board all support inloop

Loopback at an SDH Interface
Prerequisites
You must be an NE user with "NE and network operator" authority or higher.
To test whether the interface module and external cables of a board are normal, you need to set
an outloop.
To test whether the cross-connect unit and service path of the equipment are normal, you need
to set an inloop.
Impact on Services
In the case of non-protection, the loopback may interrupt the services or the communication
signals.
Tools/Instruments
T2000
Procedure
Step 1 In the Main Topology of the T2000, select the NE to be looped back.
Step 2 Right-click the NE icon in the Main Topology and select NE Explorer.
Step 3 Select the board from the Object Tree and select Configuration > SDH Interface from the
Function Tree.
Step 4 Select By Function. Select Optical (Electrical) Interface Loopback.
Step 5 Select the port and select the loopback mode Inloop or Outloop.
Step 6 Click Apply. The confirm dialog box is displayed. Click OK.
Step 7 The Operation Result dialog box is displayed and indicates that the operation is successful.
Click Close.
This article works for Huawei OptiX OSN 2500 (V100R008)

Huawei OptiX OSN 1500 Boards (3)

The Huawei Transmission OptiX OSN 1500 intelligent optical transmission system (the OptiX OSN 1500 for short) developed by Huawei is the next-generation intelligent optical transmission equipment.

The OptiX OSN 1500 is of a “universal switch” architecture. That is, the OptiX OSN 1500 can be used in packet mode or in TDM mode. When used with the other equipment of Huawei, the OptiX OSN 1500 supports various networking applications, such as the pure packet mode application, hybrid networking application (overlay networking of the packet mode and TDM mode), and pure TDM mode application. By using a proper networking solution, the data service and conventional SDH service can be processed in the optimal manner.

PDH Boards

Valid slots, interfacing modes, interface types, and connector types of the PDH boards used on the OptiX OSN 1500A

Board	Description	Valid Slot	Interfacing Mode	Interface Type	Connector Type
N1PL3A, N2PL3A	3xE3/T3 service processing board (Interfaces are available on the front panel.)	Slots 12 and 13	Interfaces available on the front panel	75-ohm E3/T3 electrical interface	SMB
R1PD1, R2PD1, R2PD1A/B	32xE1 service processing board	Slots 2 and 12	Interfaces available on a 16-port electrical switching interface board R1L75S and R1L12S	-	-
R1PL1, R1PL1A/B	16xE1 service processing board	Slots 6-9	Interfaces available on the front panel	2 mm HM connector	2 mm HM
N1PFL1	8xE1 optical processing board	Slots 12 and 13	Interfaces available on the front panel	I-2M	LC
N1DXA	DDN service converging and processing board	Slots 12 and 13	-	-	-
N3DX1	DDN service converging and processing board	Slots 12 and 13	Interfaces available on the front panel	Sub-rate service interface: RS-232 and RS-485 Pulse code modulation (PCM) service interface: FXS/FXO 2/4 wire audio and E&M	RJ-45, RJ-11

Valid slots, interface types, and connector types of the PDH interface boards used on the OptiX OSN 1500A

Board	Description	Valid Slot	Interface Type	Connector Type
R1L75S	16xE1 electrical switching interface board (75 ohms)	Slots 6 and 7	75-ohm E1 interface	DB44
R1L12S	16xE1/T1 electrical switching interface board (120 ohms)	Slots 6 and 7	120-ohm E1 interface	DB44

Valid slots, interfacing modes, interface types, and connector types of the PDH boards used on the OSN 1500B

Board	Description	Valid Slot	Interfacing Mode	Interface Type	Connector Type
N1SPQ4, N2SPQ4	4xE4/STM-1 electrical processing board	Slots 12 and 13	Interfaces available on a 4-port electrical interface board N1MU04	-	-
N2PQ3	12xE3/T3 service processing board	Slots 12 and 13	Interfaces available on a 6-port electrical switching interface board N1D34S	-	-
N1PD3, N2PD3	6xE3/T3 service processing board	Slots 12 and 13	Interfaces available on a 6-port electrical switching interface board N1D34S	-	-
N1PL3, N2PL3	3xE3/T3 service processing board	Slots 12 and 13	Interfaces available on a 3-port electrical switching interface board N1C34S	-	-
N1PL3A, N2PL3A	3xE3/T3 service processing board (Interfaces are available on the front panel.)	Slots 11-13	Interfaces available on the front panel	75-ohm E3/T3 electrical interface	SMB
N1PQ1, N2PQ1, N2PQ1A/B	63xE1 service processing board	Slots 11-13	Interfaces available on a 32-port electrical switching interface board N1D75S, N1D12S, or N1D12B	-	-
R1PD1, R2PD1, R2PD1A/B	32xE1 service processing board	Slots 1-3, 6-8, and 11-13	Interfaces available on a 32-port electrical switching interface board N1D75S, N1D12S, or N1D12B	-	-
R1PL1, R1PL1A/B	16xE1 service processing board	Slots 6-9	Interfaces available on the front panel	2 mm HM connector	2 mm HM
N1PQM	63xE1/T1 service processing board	Slots 11-13	Interfaces available on a 32-port electrical switching interface board N1D12S or N1D12B	-	-
N1DX1	DDN service accessing and converging board	Slots 11-13	Interfaces available on a DDN service interface board N1DM12	-	-
N1DXA	DDN service converging and processing board	Slots 11-13	-	-	-
N3DX1	DDN service converging and processing board	Slots 11-13	Interfaces available on a DDN service interface board N1DM12	-	-
			Interfaces available on the front panel	Sub-rate service interface: RS-232 and RS-485 Pulse code modulation (PCM) service interface: FXS/FXO 2/4 wire audio and E&M	RJ-45, RJ-11
N1PFL1	8xE1 optical processing board	Slots 11-13	Interfaces available on the front panel	I-2M	LC

Valid slots, interface types, and connector types of the PDH interface boards used on the OptiX OSN 1500B

Board	Description	Valid Slot	Interface Type	Connector Type
N1DM12	DDN service interface board	Slots 14-17	Framed E1 interface Nx64 kbit/s interface: V.35, V.24, X.21, RS-449, RS-530, RS-530A Sub-rate interface: RS-232, RS-422, X.21, V.35, V.24 G.703 64 kbit/s codirectional interface: Co64K	DB28, DB44
N1MU04	4xE4/STM-1 electrical interface board	Slots 14 and 16	75-ohm E4/STM-1 electrical interface	SMB
N1C34S	3xE3/T3 electrical switching interface board	Slots 14 and 16	75-ohm E3/T3 electrical interface	SMB
N1D34S	6xE3/T3 electrical switching interface board	Slots 14-17	75-ohm E3/T3 electrical interface	SMB
N1D75S	32xE1 electrical switching interface board (75 ohms)	Slots 14-17	75-ohm E1 interface	DB44
N1D12S	32xE1/T1 electrical switching interface board (120 ohms)	Slots 14-17	120-ohm E1 interface 100-ohm T1 interface	DB44
N1D12B	32xE1/T1 electrical switching interface board	Slots 14-17	75-ohm/120-ohm E1 interface 100-ohm T1 interface	DB44
N1TSB8	8-port electrical switching interface board	Slots 14 and 15	-	-
N1TSB4	4-port electrical switching interface board	slot 14	-	-

As a world leading Huawei networking products supplier, Thunder-link wholesales original new Huawei networking equipments, including Huawei switches, Huawei routers, Huawei symantec security products, Huawei IAD, Huawei SFP and other Huawei networking products. Our customers include telecom operators, Huawei resellers, ISP and system integrators. If you have such requirement please contact your sales person, if you are new customer, please feel free to contact sales@thunder-link.com. Our HCIE headed technical team can provide network design, products installation and configuration, trouble shooting etc.

Contact information:

Telephone: 852-30623083

Email: Sales@Thunder-Link.com

           Supports@Thunder-link.com            

Website: http://www.thunder-link.com

More related:

Huawei OSN 1500 Overview

Huawei OSN 1500 Platinum Line  Overview

Huawei OSN 1500 Gold Line Overview
Huawei OSN 1500 Silver Line Overview
Huawei OptiX OSN 1500 Boards (1)
Huawei OptiX OSN 1500 Boards (2)

Huawei OptiX OSN 1500 Boards (2)

The Huawei OptiX OSN 1500 intelligent optical transmission system (the OptiX OSN 1500 for short) developed by Huawei is the next-generation intelligent optical transmission equipment.

The OptiX OSN 1500 is of a “universal switch” architecture. That is, the OptiX OSN 1500 can be used in packet mode or in TDM mode. When used with the other equipment of Huawei, the OptiX OSN 1500 supports various networking applications, such as the pure packet mode application, hybrid networking application (overlay networking of the packet mode and TDM mode), and pure TDM mode application. By using a proper networking solution, the data service and conventional SDH service can be processed in the optimal manner.

SDH Boards

Valid slots, interfacing modes, interface types, and connector types of the SDH boards used on the OptiX OSN 1500A

Board	Description	Valid Slot	Interfacing Mode	Interface Type	Connector Type
N1SL16, N2SL16	1xSTM-16 optical interface board	Slots 12 and 13	Interfaces available on the front panel	L-16.2, L-16.2Je, V-16.2Je, U-16.2Je	LC
N3SL16	1xSTM-16 optical interface board	Slots 12 and 13	Interfaces available on the front panel	L-16.2, L-16.2Je, V-16.2Je, U-16.2Je Colored optical interface types: DWDM (170 km) and DWDM (640 km)	LC
N1SL16A, N2SL16A	1xSTM-16 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-16, S-16.1, L-16.1, L-16.2	LC
N3SL16A	1xSTM-16 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-16, S-16.1, L-16.1, L-16.2, U-16.2Je Colored optical interface types: CWDM (80 km) and DWDM (120 km)	LC
N1SF16	1xSTM-16 optical interface board (with outband FEC)	Slots 12 and 13	Interfaces available on the front panel	Ue-16.2c, Ue-16.2d, Ue-16.2f	LC
N1SF16E	1xSTM-16 optical interface board (with outband EFEC)	Slots 12 and 13	Interfaces available on the front panel	Colored optical interface type: DWDM (120 km)	LC
N1SLQ4, N1SLQ4A, N2SLQ4	4xSTM-4 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SLD4, N1SLD4A, N2SLD4	2xSTM-4 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
R1SLD4	2xSTM-4 optical interface board (divided slot)	Slots 2, 3, 6-9, 12, and 13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SL4, N2SL4	1xSTM-4 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SL4A	1xSTM-4 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2 Colored optical interface types: CWDM (80 km) and DWDM (120 km)	LC
N3SLQ41	4xSTM-4/STM-1 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-1/I-4, S-1.1/S-4.1, L-1.1/L-4.1, L-1.2/L-4.2, Ve-1.2/Ve-4.2 Colored optical interface types: CWDM (80 km) and DWDM (120 km)	LC
R1SL4	1xSTM-4 optical interface board (divided slot)	Slots 2, 3, 6-9, 12, and 13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SLT1	12xSTM-1 optical interface board	Slots 12 and 13	Interfaces available on the front panel	S-1.1, L-1.1, L-1.2	LC
N2SLO1, N3SLO1	8xSTM-1 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-1, S-1.1, L-1.1, L-1.2, Ve-1.2	LC
N1SLQ1, N1SLQ1A, N2SLQ1	4xSTM-1 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-1, S-1.1, L-1.1, L-1.2, Ve-1.2, Ie-1	LC
R1SLQ1	4xSTM-1 optical interface board (divided slot)	Slots 2, 3, 6-9, 12, and 13	Interfaces available on the front panel	I-1, S-1.1, L-1.1, L-1.2, Ve-1.2, Ie-1	LC
N1SL1, N1SL1A, N2SL1	1xSTM-1 optical interface board	Slots 12 and 13	Interfaces available on the front panel	I-1, S-1.1, L-1.1, L-1.2, Ve-1.2	LC
R1SL1	1xSTM-1 optical interface board (divided slot)	Slots 2, 3, 6-9, 12, and 13	Interfaces available on the front panel	I-1, Ie-1, S-1.1, L-1.1, L-1.2, Ve-1.2	LC
N1SEP1	2xSTM-1 line processing board	Slots 12 and 13	Interfaces available on the front panel	75-ohm STM-1 electrical interface	SMB

Valid slots, interfacing modes, interface types, and connector types of the SDH boards used on the Huawei OptiX OSN 1500B

Board	Description	Valid Slot	Interfacing Mode	Interface Type	Connector Type
N1SL16, N2SL16	1xSTM-16 optical interface board	Slots 11-13	Interfaces available on the front panel	L-16.2, L-16.2Je, V-16.2Je, U-16.2Je	LC
N3SL16	1xSTM-16 optical interface board	Slots 11-13	Interfaces available on the front panel	L-16.2, L-16.2Je, V-16.2Je, U-16.2Je Colored optical interface types: DWDM (170 km) and DWDM (640 km)	LC
N1SL16A, N2SL16A	1xSTM-16 optical interface board	Slots 11-13	Interfaces available on the front panel	I-16, S-16.1, L-16.1, L-16.2	LC
N3SL16A	1xSTM-16 optical interface board	Slots 11-13	Interfaces available on the front panel	I-16, S-16.1, L-16.1, L-16.2, U-16.2Je Colored optical interface types: CWDM (80 km) and DWDM (120 km)	LC
N1SF16	1xSTM-16 optical interface board (with outband FEC)	Slots 11-13	Interfaces available on the front panel	Ue-16.2c, Ue-16.2d, Ue-16.2f Colored optical interface type: DWDM (640 km)	LC
N1SF16E	1xSTM-16 optical interface board (with outband EFEC)	Slots 11-13	Interfaces available on the front panel	Colored optical interface type: DWDM (120 km)	LC
N1SLQ4, N1SLQ4A, N2SLQ4	4xSTM-4 optical interface board	Slots 11-13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SLD4, N1SLD4A, N2SLD4	2xSTM-4 optical interface board	Slots 11-13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
R1SLD4	2xSTM-4 optical interface board (divided slot)	Slots 1-3 and 11-13 (two optical interfaces can be configured), and slots 6-9 (one optical interface can be configured)	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SL4, N2SL4	1xSTM-4 optical interface board	Slots 11-13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SL4A	1xSTM-4 optical interface board	Slots 11-13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2 Colored optical interface types: CWDM (80 km) and DWDM (120 km)	LC
N3SLQ41	4xSTM-4/STM-1 optical interface board	Slots 11-13	Interfaces available on the front panel	I-1/I-4, S-1.1/S-4.1, L-1.1/L-4.1, L-1.2/L-4.2, Ve-1.2/Ve-4.2 Colored optical interface types: CWDM (80 km) and DWDM (120 km)	LC
R1SL4	1xSTM-4 optical interface board (divided slot)	Slots 1-3, 6-9, and 11-13	Interfaces available on the front panel	I-4, S-4.1, L-4.1, L-4.2, Ve-4.2	LC
N1SLT1	12xSTM-1 optical interface board	Slots 11-13	Interfaces available on the front panel	S-1.1, L-1.1, L-1.2	LC
N2SLO1, N3SLO1	8xSTM-1 optical interface board	Slots 11-13	Interfaces available on the front panel	I-1, S-1.1, L-1.1, L-1.2, Ve-1.2	LC
N1SLQ1, N1SLQ1A, N2SLQ1	4xSTM-1 optical interface board	Slots 11-13	Interfaces available on the front panel	I-1, S-1.1, L-1.1, L-1.2, Ve-1.2, Ie-1	LC
R1SLQ1	4xSTM-1 optical interface board (divided slot)	Slots 1-3, 6-9, and 11-13	Interfaces available on the front panel	I-1, Ie-1, S-1.1, L-1.1, L-1.2, Ve-1.2	LC
N1SL1, N1SL1A, N2SL1	1xSTM-1 optical interface board	Slots 11-13	Interfaces available on the front panel	I-1, S-1.1, L-1.1, L-1.2, Ve-1.2	LC
R1SL1	1xSTM-1 optical interface board (divided slot)	Slots 1-3, 6-9, and 11-13	Interfaces available on the front panel	I-1, Ie-1, S-1.1, L-1.1, L-1.2, Ve-1.2	LC
N1SEP1 (with an interface board)	8xSTM-1 line processing board	Slots 12 and 13	Interfaces available on a 4xSTM-1 electrical interface board N1EU04	–	–
			Interfaces available on an 8xSTM-1 optical interface board N1OU08	–	–
			Interfaces available on an 8xSTM-1 optical interface board N2OU08	–	–
			Interfaces available on an 8xSTM-1 electrical interface board N1EU08	–	–
N1SEP1 (without an interface board)	2xSTM-1 line processing board	Slots 11-13	Interfaces available on the front panel	75-ohm STM-1 electrical interface	SMB
N1EU04	4xSTM-1 electrical interface board	Slots 14 and 16	Interfaces available on the front panel	75-ohm STM-1 electrical interface	SMB
N1EU08	8xSTM-1 electrical interface board	Slots 14 and 16	Interfaces available on the front panel	75-ohm STM-1 electrical interface	SMB
N1OU08	8xSTM-1 optical/electrical interface board	Slots 14 and 16	Interfaces available on the front panel	S-1.1	LC
N2OU08	8xSTM-1 optical interface board	Slots 14 and 16	Interfaces available on the front panel	S-1.1	SC
NOTE: An SEP1 board is displayed as SEP1 or SEP on the NMS, depending on the interfacing mode of the board. When an SEP1 provides interfaces on its front panel, it is displayed as SEP1 on the NMS; when it is used with an interface board, it is displayed as SEP on the NMS.

As a world leading Huawei networking products supplier, Thunder-link wholesales original new Huawei networking equipments, including Huawei switches, Huawei routers, Huawei symantec security products, Huawei IAD, Huawei SFP and other Huawei networking products. Our customers include telecom operators, Huawei resellers, ISP and system integrators. If you have such requirement please contact your sales person, if you are new customer, please feel free to contact sales@thunder-link.com. Our HCIE headed technical team can provide network design, products installation and configuration, trouble shooting etc.

Contact information:

Telephone: 852-30623083

Email: Sales@Thunder-Link.com

           Supports@Thunder-link.com            

Website: http://www.thunder-link.com

More related:

Huawei OSN 1500 Overview

Huawei OSN 1500 Platinum Line  Overview

Huawei OSN 1500 Gold Line Overview
Huawei OSN 1500 Silver Line Overview
Huawei OptiX OSN 1500 Boards (3)

Huawei OptiX OSN 1500 Boards (1)

Huawei OptiX OSN 1500 Boards (1)

The Huawei OptiX OSN 1500 intelligent optical transmission system (the OptiX OSN 1500 for short) developed by Huawei is the next-generation intelligent optical transmission equipment.

The OptiX OSN 1500 is of a “universal switch” architecture. That is, the OptiX OSN 1500 can be used in packet mode or in TDM mode. When used with the other equipment of Huawei, the OptiX OSN 1500 supports various networking applications, such as the pure packet mode application, hybrid networking application (overlay networking of the packet mode and TDM mode), and pure TDM mode application. By using a proper networking solution, the data service and conventional SDH service can be processed in the optimal manner.

Huawei OSN Cross-Connect Boards and System Control Boards

Valid slots, interfacing modes, interface types, and connector types of the SCC unit, cross-connect unit, timing unit, and line unit integrated boards used on the OptiX OSN 1500

Board	Description	Valid Slot	Interfacing Mode	Interface Type	Connector Type
R1PCXLN	SCC unit, cross-connect unit, and optical interface unit integrated board (supporting packet features)	Slots 4 and 5	Interfaces available on the front panel	S-1.1, L-1.1, L-1.2, S-4.1, L-4.1, L-4.2, Ve-4.2, I-16, S-16.1, L-16.1, L-16.2 Colored optical interface types: CWDM (80 km) and DWDM (120 km)	LC
NOTE: A PCXL board is a cross-connect unit, timing unit, SCC unit, and line unit integrated board used in an OptiX OSN 1500A subrack. It is a physical board and is housed in slots 4-5. On the NMS, the R1PCXLN board is displayed as Q2SLN (in logical slots 4-5), PCXL (in logical slots 80-81), and GSCC (in logical slots 82-83) boards.

Packet Processing Boards

Valid slots, interfacing modes, interface types, and connector types of the packet processing boards used on the OptiX OSN 1500

Board	Description	Valid Slot	Interfacing Mode	Interface Type	Connector Type
Q1PEGS2	2xGE processing board	Slots 12 and 13	Interfaces available on the front panel	1000BASE-SX/LX/ZX/VX Colored optical interface type: CWDM (40 km)	LC
				1000BASE-T	RJ-45
R1PEGS1	1xGE processing board	Slots 2, 3, 6-9, 12, and 13	Interfaces available on the front panel	1000BASE-SX/LX/ZX/VX Colored optical interface type: CWDM (40 km)	LC
				1000BASE-T	RJ-45
R1PEFS8	8xFE processing board	Slots 2, 3, 6-9, 12, and 13	Used with a high-density transfer box with FE interfaces	Delander	RJ-45
R1PEF4F	4xFE optical interface board	Slots 6-9, 12, and 13	Interfaces available on the front panel	100BASE-FX/LX	LC
R1ML1	Multi-protocol 16xE1 electrical processing board	Slots 6-9	Interfaces available on the front panel	75/120-ohm E1 interface	2mmHM

As a world leading Huawei networking products supplier, Thunder-link wholesales original new Huawei networking equipments, including Huawei switches, Huawei routers, Huawei symantec security products, Huawei IAD, Huawei SFP and other Huawei networking products. Our customers include telecom operators, Huawei resellers, ISP and system integrators. If you have such requirement please contact your sales person, if you are new customer, please feel free to contact sales@thunder-link.com. Our HCIE headed technical team can provide network design, products installation and configuration, trouble 

Contact information:

Telephone: 852-30623083

Email: Sales@Thunder-Link.com

           Supports@Thunder-link.com            

Website: http://www.thunder-link.com

More related:

Huawei OSN 1500 Overview

Huawei OSN 1500 Platinum Line  Overview

Huawei OSN 1500 Gold Line Overview
Huawei OSN 1500 Silver Line Overview

Huawei OptiX OSN 1500 Boards (2)
Huawei OptiX OSN 1500 Boards (3)

How to Troubleshoot Synchronous Ethernet Clocks For Huawei SDH

How to Troubleshoot Synchronous Ethernet Clocks For Huawei SDH

OptiX OSN 7500 II/7500/ OptiX OSN 3500/ OptiX OSN 1500 Troubleshooting：How to Troubleshoot Synchronous Ethernet Clocks

The common faults regarding the synchronous Ethernet clock are as follows:

A clock source cannot be properly switched and the quality of clock is low.

Possible Causes

l The connection at the port fails.

l An alarm associated with the synchronous Ethernet clock function occurs on the network.

Figure 1 Flow chart for handling a synchronous Ethernet clock fault

Procedure

Step 1 Cause 1: The connection at the port fails.

1. Check whether the ETH_LOS or ETH_LINK_DOWN alarm occurs at the port.

2. If yes, clear the alarm and then check whether the fault is rectified. For details on how to

clear the alarm, see the Alarms and Performance Events Reference.

Step 2 Cause 2: An alarm associated with the synchronous Ethernet clock occurs on the network.

1. Check whether any alarm associated with the synchronous Ethernet clock occurs on the network. For details, see Relevant Alarms.

2. If yes, clear the alarm. For details on how to clear the alarm, see the Alarms and

Performance Events Reference.

Step 3 If the fault persists, contact Huawei technical support engineers to handle the fault.

—-End