Monitoring events in IBM InfoSphere Change Data Capture with CHCCLP

Monitor events and system messages that relate to the subscription for your shadow tables to check replication activity and identify problems with the subscription by using the CHCCLP command-line interface.

To monitor events in InfoSphere CDC:

1. Log into the access-server-host as cdc-user.
2. Start the CHCCLP command-line interface for InfoSphere CDC by issuing the following command:

   $ /access-server-installation-dir/bin/chcclp 

3. Connect to the access server by issuing the connect server command as follows:

   connect server hostname access-server-host port access-server-port
           username access-server-user password access-server-user-password;

4. Connect to the datastore that you configured in Setting up the datastore for shadow tables with commands for IBM InfoSphere CDC Access Server and indicate as a source and target for subsequent commands by issuing the connect datastore command as follows:

   connect datastore name access-server-datastore-name;
   

5. Retrieve status information for the subscription by issuing the monitor replication command as follows:

   monitor replication;

   The following text is an extract of the command output for a subscription called SUB1:

   SUBSCRIPTION     STATE            SOURCE DATASTORE   TARGET DATASTORE
   ---------------- ---------------- ------------------ ------------------
   SUB1             Failed           shadowds           shadowds

6. If the status is Failed, list the events of the shadow table subscription by issuing the list subscription events command as follows:

   list subscription events type source count 100;
   

   This command returns the most recent 100 events. The following text is sample output that shows the last four events, including truncated error messages that are related to an event that caused replication to stop:

   ROW EVENT ID TYPE        OBJECT MESSAGE
   --- -------- ----------- ------ -------------------------------------------------
   1   93       Information SUB1   *** IBM InfoSphere Change Data Capture is ending.
   2   1465     Error       SUB1   --- Subscription SUB1 is terminating abnormally.
   3   1713     Error       SUB1   IBM InfoSphere Change Data Capture to SUB1
                                   is initiating shutdown due to f...
   4   9505     Error       SUB1   IBM InfoSphere Change Data Capture has
                                   encountered a critical data definition (DDL)
                                   change...

7. Extract the full text of truncated messages and event details by issuing the show subscription event details command as follows:

   show subscription event details row row-number;

   The following text is sample output that shows why replication ended:

   EVENT ID:           9505
   TYPE:               Error
   TIME:               Jul 17, 2014 10:50:15 AM
   
   MESSAGE:
   IBM InfoSphere Change Data Capture has encountered a critical data
   definition (DDL) change for source table DTW.TRADE and will shutdown.
   In order to resume replication for this table you must do the following
   before restarting the subscription.
    1) Update the Source Table definition and verify that the resulting table
   mapping is correct.
    2) Provide a new replication synchronization point by either refreshing
   the table via the product (Flag for Refresh) or setting the table
   active (Mark Table Capture Point for Mirroring) and manually ensuring
   that the target table is in synch.