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Procedure documentationMonitoring the Lock Table at Failover Locate this document in the navigation structure

 

By running the tests in program enqt you can check and monitor the fill level and the ID of the Lock Table.

Prerequisites

You have started the (A)SCS instance of your SAP system. With an ABAP+Java system both the SCS instance and the ASCS instance must be running.

Start program enqt on the server on which the replication server is installed.

Procedure

Caution Caution

Then use the enqt options described here. Otherwise you could damage the content of the lock table.

End of the caution.
Monitoring the Fill Level of the Lock Table During Failover
  1. Enter the command below to fill the lock table of the enqueue server with 20 locks.

    enqt pf=<ERS_instance_profile> 11 20

    Here <ERS_instance_profile> is the profile that was created when the replication server was installed.

  2. Monitor the fill level of the lock table by executing the command below:

    enqt pf=<ERS_instance_profile> 20 1 1 9999

    This command permantly reads the content of the lock table and shows the number of lock entries on the console.

  3. Trigger a failover of the (A)SCS (the exact procedure depends on the cluster solution used).

    The output will look like this:

    Number of selected entries: 20

    Number of selected entries: 20

    Number of selected entries: 20

    Number of selected entries: 20

    Number of selected entries: 20

    Number of selected entries: 0 (Failover)

    Number of selected entries: 20 (Enqueue server is running again)

    Number of selected entries: 20

    Number of selected entries: 20

    Number of selected entries: 20

    Number of selected entries: 20

    ...

  4. Make sure that the number of lock entries is the same both before and after the failover. If the enqueue ID changes, or the number of locks is zero after the failover, the replica was not copied. Using level 3 trace you have to run a detailed analysis of the failover (in particular of the enqueue server that was restarted).

    • You can now check whether the instance number of the replication server and the instance number of the enqueue server matches. If it doesn’t, there is a configuration error. Use showipc to check whether there is a shared memory segment with number 66. Check whether the enqueue server has been started on the correct host (the host on which the replication was running before).

    • Search in trace files dev_enqsrv (after the failover) and dev_enrepsrv (before the failover) for error messages.

    • Contact SAP Support.

Monitoring Lock Table ID During Failover
  1. Enter the following command to output the lock table ID before the failover.

    enqt pf=<ERS_instance_profile> 97

    Here <ERS_instance_profile> is the profile that was created when the replication server was installed.

  2. Trigger a failover of the (A)SCS instance.

  3. Enter the command enqt pf=<ERS_instance_profile> 97.

    The result should look like:

    Before the failover:

    enqt =<ERS_instance_profile> 97

    ---REQ----------------------------------------------------------

    EnqId: EnqTabCreaTime/RandomNumber = 25.10.2005 11:15:59 1130231759

    / 9288

    ...

    After the failover:

    enqt =<ERS_instance_profile> 97

    ---REQ----------------------------------------------------------

    EnqId: EnqTabCreaTime/RandomNumber = 25.10.2005 11:15:59 1130231759

    / 9288

    ...

  4. Make sure that the lock table ID is the same before and after the failover. If it isn’t, the replica has not been copied (see above).