Why Does GoldenGate Report The Lag Is Unknown

Solution

Issue:
     Why does GoldenGate report the Lag is unknown?  The "Lag" command fails with "Timestamp Mismatch".  Sometimes the "Info All" will also show the Lag is unknown.


Solution Overview:
    (1) Lag Command(after handling one or more records)

             GGSCI > lag extract e1
             Sending GETLAG request to EXTRACT E1...
             Lag unknown (timestamp mismatch between source and target).
             At EOF, no more records to process.

    (2) "Info All"(This may happen after handling a large amount of records)

             GGSCI > info all
             Program Status Group Lag Time Since Chkpt
             MANAGER RUNNING
             EXTRACT RUNNING E1 unknown 00:00:04

    (3) "showch" and date timestamp mismatch

             GGSCI > info e1 showch
              ...
             Checkpoint Lag unknown (updated 00:00:03 ago)
             Log Read Checkpoint File /rdbms/oracle/ora1022i/64/oradata/ora1022a/redo01.log
             2007-03-12 13:36:48 Seqno 3724, RBA 32885344
             .....
             GGSCI > sh date
             Mon Mar 12 12:37:08 PDT 2007

Solution Details:

    Set the correct timezone TZ environmental parameter.

    Example

        $ > env |grep TZ
        TZ=PST9PDT
        $ > date
        Mon Mar 12 12:40:57 PDT 2007
        $ > export TZ=PST8PDT
        $ > date
        Mon Mar 12 13:41:08 PDT 2007
        You must re-start the Manager and all other GoldenGate groups.