The principles of DLAG feature of Huawei DWDM Equipment

When the main board like Huawei TN52SCC on Huawei OSN8800 or OSN6800  detects a failed port, the cross-connect board switches the services carried by the failed port from the main board to the slave board to protect the services.

Figure 1 shows the processing flow of a DLAG.

Figure 1 Processing flow of a DLAG 

In the transmit direction, the processing flow of the DLAG is described as follows:

• The cross-connect board of NE1 transmits the services to the main board and slave board of the DLAG. Then, the main board and slave board of the DLAG transmit the services to the equipment at the opposite end.
• When a link down failure, a board offline event, or a hardware failure occurs on the main board, the equipment at the opposite end receives the signals sent by the slave board.

In the receive direction, the processing flow of the DLAG is described as follows:

• The main board and slave board of NE1 transmit the main services and slave services sent from the opposite end respectively to the cross-connect board of NE1. The cross-connect board of NE1 selects services between the main services and slave services.
• When the main board works normally, the cross-connect board selects the services sent by the main board.
• When the main board detects a link down failure, a board offline event, or a hardware failure, the cross-connect board selects the services sent by the slave board to protect the services.

How to Back Up the NE Database to the SCC Board on Huawei DWDM Equipment?

You need to back up the NE database during daily maintenance, to ensure that Huawei TN52SCC board of the NE automatically restores to normal operation after a data loss or equipment power failure. When you back up the NE database to the SCC board, you actually back up the NE data in the DRDB database of the SCC board to the Flash database. When the NE is restarted after a power failure, the SCC board automatically reads the configuration from the FLASH and issues the configuration to the boards.

Prerequisite

You are an NMS user with "Administrators" privilege.

You must log in to the NE as an NE user with system level authority.

Tools, Equipment and Materials

U2000 or Web LCT

Precautions

By default, the NMS automatically backs up the NE database into the flash memory every 30 minutes.

Procedure on the U2000

1. Visit the following navigation path.
   
2. Back up the NE database to the SCC board on Huawei OSN 6800.
   

Procedure on the Web LCT

1. Select one or more NEs in the NE list. Click BackUp NE Database > BackUp to SCC.
   The NMS takes a few minutes to back up the NE database. Do not perform any operation in the process of backup.
2. Click OK in the confirmation dialog box.
3. Click Close in the Operation Result dialog box is displayed.