How to Do If the Optical Interfaces Connected by a Fiber Cannot be Up?

Before checking a link, check whether the LINK indicator of the interface is on. If the indicator is on, the physical link is normal. Perform the following steps:

1. Check whether either of the interfaces is shut down. If an interface is shut down, run the undo shutdown command on it.

2. If the shutdown command is not used, check whether either of the two connected optical interfaces is the combo interface. If yes, run the display this interfacecommand to check whether the interface is FORCE FIBER. If not, run the combo-port fiber command to change the interface to the forcible optical interface.

   [HUAWEI-GigabitEthernet0/0/1] display this interface
   ......
   Port Mode: FORCE FIBER
   Speed : 1000,  Loopback: NONE
   Duplex: FULL,  Negotiation: ENABLE
   Mdi   : NORMAL
   ......
   

3. If the two interfaces are both optical interfaces but cannot be Up, it is possible that one interface is an FE interface and the other is a GE interface. In this case, you need to disable auto-negotiation on the GE interface, set the operation mode of the GE interface to 100 Mbit/s, and set the duplex mode to full duplex. Check whether the interfaces become Up. If they are still down, contact technical support personnel.

4. If the two interfaces are both GE interfaces, check whether the auto-negotiation status, rates, and duplex modes on the two interfaces are the same. If they are different, set them to be the same.

5. If the interfaces are still Down, ensure that input optical power on each interface is within the receiver sensibility of the interface.

6. If the problem persists, contact technical support personnel.