No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search


To have a better experience, please upgrade your IE browser.


OSN 500 550 580 V100R008C50 Alarms and Performance Events Reference 02

Rate and give feedback :
Huawei uses machine translation combined with human proofreading to translate this document to different languages in order to help you better understand the content of this document. Note: Even the most advanced machine translation cannot match the quality of professional translators. Huawei shall not bear any responsibility for translation accuracy and it is recommended that you refer to the English document (a link for which has been provided).



The OCD alarm indicates that the cell delimitation state machine is in the hunt or presyn state.


Alarm Severity Alarm Type


Communication alarm



Impact on the System

All the services in the receive direction of the port are intermittently transmitted. Consequently, cells are lost.

Possible Causes

Possible causes of the OCD alarm are as follows:

  • A great number of bit errors occur in the SDH receive path connected to the alarmed port. That is, bit error alarms, such as B1_SD, B2_SD, or B3_SD, are reported.
  • The ATM processing chip on the alarmed board is faulty.


  1. On the U2000, check whether the B1_EXC, B2_EXC, or B3_EXC alarm which indicates bit errors on the tributary board exceeds the threshold is reported on the local NE.
    If... Then...

    The B1_EXC, B2_EXC, or B3_EXC alarm is reported

    Handle the alarms, and then check whether the OCD alarm is cleared. If the OCD alarm persists, go to the next step.

    The B1_EXC, B2_EXC, or B3_EXC alarm is not reported

    Go to the next step.

  2. Reset (cold) or reseat the board that reports the OCD alarm. Then, check whether the OCD alarm is cleared.

    If the services on the alarmed board are not protected, a cold reset on the board causes service interruption.

  3. If the OCD alarm persists, replace the board and check whether the OCD alarm is cleared. If the OCD alarm persists, contact Huawei technical support engineers to handle the alarm.

Related Information


Updated: 2019-01-21

Document ID: EDOC1100020975

Views: 75281

Downloads: 138

Average rating:
This Document Applies to these Products
Related Documents
Related Version
Previous Next