What Can I Do If the Optical Power Is Low or High?

Fault Description

Optical power alarms occur when two optical interfaces are connected to each other.

Optical Power Alarms

BASETRAP_1.3.6.1.4.1.2011.5.25.129.2.17.1 hwOpticalPowerAbnormal     //An alarm indicating abnormal transmit or receive power of an optical module.
BASETRAP/3/OPTPWRABNORMAL: OID [oid] Optical module power is abnormal. (EntityPhysicalIndex=[INTEGER], BaseTrapSeverity=[INTEGER],
 BaseTrapProbableCause=[INTEGER], BaseTrapEventType=[INTEGER], EntPhysicalContainedIn=[INTEGER], EntPhysicalName="[OCTET]", Relati
veResource="[OCTET]", ReasonDescription="[OCTET]")

ENTITYTRAP_1.3.6.1.4.1.2011.5.25.219.2.4.5 hwOpticalInvalid 136193   //An alarm indicating a high transmit power of an optical module.
ENTITYTRAP_1.3.6.1.4.1.2011.5.25.219.2.4.5 hwOpticalInvalid 136194   //An alarm indicating a low transmit power of an optical module.
ENTITYTRAP_1.3.6.1.4.1.2011.5.25.219.2.4.5 hwOpticalInvalid 136195   //An alarm indicating a high receive power of an optical module.
ENTITYTRAP_1.3.6.1.4.1.2011.5.25.219.2.4.5 hwOpticalInvalid 136196   //An alarm indicating a low receive power of an optical module.
ENTITYTRAP/3/OPTICALINVALID:OID [oid] Optical Module is invalid.(Index=[INTEGER], EntityPhysicalIndex=[INTEGER], PhysicalName=\"
[OCTET]\", EntityTrapFaultID=[INTEGER])

Possible Causes

• The type and wavelength of the local and remote optical modules are inconsistent.
• The optical module is incorrectly installed or the optical fiber is faulty.
• The fiber is too long or the fiber attenuation is too high.
• The remote transmit power is out of the allowed range.
• The optical module is faulty.

Troubleshooting Procedure

You are advised to save the results of each troubleshooting step. This information will help Huawei technical support assist you if the fault persists.

1. Check whether the local and remote optical modules have the same wavelength.

   Run the display transceiver [ interface interface-type interface-number | slot slot-id ] [ verbose ] command to check optical module information on the interface. The Wavelength(nm) field in the command output indicates the wavelength of an optical module. If the two optical modules have different wavelengths, replace one optical module to ensure that the two optical modules have the same wavelength.

   If the fault persists, go to step 2.

2. Check the link connection.

   Remove and reinstall the fiber and optical module to ensure they are properly connected. Check whether the fiber connector is dirty or damaged. If so, clean or replace the connector.

   If the fault persists, go to step 3.

3. Check the fiber length.

   The fiber length must be shorter than the maximum transmission distance of an optical module. For the maximum transmission distance supported by different optical modules, see Optical Module in the hardware description. If the fiber length exceeds the maximum transmission distance of the optical modules, shorten the fiber length or use optical modules with a longer transmission distance.

   If the fault persists, go to step 4.

4. Check the transmit optical power on the remote device.

   Ensure that the transmit optical power on the remote device exceeds the lower threshold.

   If the fault persists, go to step 5.

5. Check whether the fiber type matches the optical module.

   Ensure that the fiber type matches the optical module:

   • A multimode fiber, generally distinguished by an orange outer sheath, is used together with a multimode optical module.
   • A single-mode fiber, generally distinguished by a yellow outer sheath, is used with a single-mode optical module.
   • Two connected optical modules must have the same wavelength.

   If the fault persists, go to step 6.

6. Check the optical module type and vendor.

   Check whether the local and remote devices use the same type of optical modules from the same vendor. If the connected optical modules have the same wavelength and provide short-distance transmission but alarms indicating low or high optical power occur, the two optical modules may be from different vendors. Although these optical modules have the same wavelength, optical power alarms occur because different vendors design different optical power indicators for these optical modules. To rectify the fault, use optical modules from the same vendor.

   If the fault persists, go to step 7.

7. Replace the parts.

   Perform a short fiber loopback test. If the fault cannot be located, replace the optical module or fiber.

   If the fault persists, go to step 8.

8. Collect the following information and contact Huawei technical support:
   • Results of the preceding troubleshooting procedure
   • Configuration file, logs, and alarms of the device