1920: Global and Metro Mirror persistent error.

Explanation

This error might be caused by a problem on the primary system, a problem on the secondary system, or a problem on the intersystem link. The problem might be a failure of a component, a component becoming unavailable or having reduced performance because of a service action, or it might be that the performance of a component dropped to a level where the Metro Mirror or Global Mirror relationship cannot be maintained. Alternatively the error might be caused by a change in the performance requirements of the applications that are using Metro Mirror or Global Mirror.

This error is reported on the primary system when the copy relationship has not progressed sufficiently over a period. Therefore, if the relationship is restarted before all of the problems are fixed, the error might be reported again when the time period next expires (the default period is 5 minutes).

This error might also be reported because the primary system has encountered read errors.

You might need to refer to the Copy Services features information in the software installation and configuration documentation while you diagnose this error.

User Response

  1. If the 1920 error has occurred previously on Metro Mirror or Global Mirror between the same systems and all the following actions have been attempted, contact your product support center to resolve the problem.
  2. On both systems, check the partner fc port mask to ensure that there is sufficient connectivity. If the partner fc port mask was changed recently, ensure that the mask is correct.
  3. On the primary system that is reporting the error, correct any higher priority errors.
  4. On the secondary system, review the maintenance logs to determine whether the system was operating with reduced capability at the time the error was reported. The reduced capability might be because of a software upgrade, hardware maintenance to a node, maintenance to a backend disk system or maintenance to the SAN.
  5. On the secondary system, correct any errors that are not fixed.
  6. On the intersystem link, review the logs of each link component for any incidents that would cause reduced capability at the time of the error. Ensure that the problems are fixed.
  7. If a reason for the error has been found and corrected, go to Action 11.
  8. On the primary system that is reporting the error, examine the statistics using a SAN productivity monitoring tool and confirm that all the Metro Mirror and Global Mirror requirements that are described in the planning documentation are met. Ensure that any changes to the applications that use Metro Mirror or Global Mirror have been taken into account. Resolve any issues.
  9. On the secondary system, examine the statistics by using a SAN productivity monitoring tool and confirm that all the Metro Mirror and Global Mirror requirements described in the software installation and configuration documentation are met. Resolve any issues.
  10. On the intersystem link, examine the performance of each component by using an appropriate SAN productivity monitoring tool to ensure that they are operating as expected. Resolve any issues.
  11. Mark the error as "fixed" and restart the Metro Mirror or Global Mirror relationship.

When you restart the Metro Mirror or Global Mirror relationship there is an initial period during which Metro Mirror or Global Mirror performs a background copy to resynchronize the volume data on the primary and secondary systems. During this period the data on the Metro Mirror or Global Mirror auxiliary volumes on the secondary system is inconsistent and the volumes cannot be used as backup disks by your applications.

Note: To ensure the system has the capacity to handle the background copy load, you might want to delay restarting the Metro Mirror or Global Mirror relationship until there is a quiet period when the secondary system and the SAN fabric (including the intersystem link) have the required capacity. If the required capacity is not available you might experience another 1920 error and the Metro Mirror or Global Mirror relationship will stop in an inconsistent state.

Note: If the Metro Mirror or Global Mirror relationship has stopped in a consistent state ("consistent-stopped") it is possible to use the data on the Metro Mirror or Global Mirror auxiliary volumes on the secondary system as backup disks by your applications. You might therefore want to start a Flash Copy of your Metro Mirror or Global Mirror auxiliary disks on the secondary system before restarting the Metro Mirror or Global Mirror relationship. This means you maintain the current, consistent, image until the time when the Metro Mirror or Global Mirror relationship is again synchronized and in a consistent state.

Possible Cause-FRUs or other:

Other:

Parent topic: Error event IDs and error codes