4 Replies Latest reply: Oct 31, 2012 3:40 AM by ozgurumut RSS

    gap in archive log

    929456
      hi,
      what happens if there is a gap of 100 archivelogs in between primary and standby database.
      how to fill that gap?
      please some one let me know
        • 1. Re: gap in archive log
          teits
          926453 wrote:
          hi,
          what happens if there is a gap of 100 archivelogs in between primary and standby database.
          how to fill that gap?
          please some one let me know
          when what caused the redo gap is resolved(e.g network issue), the redo transport services automatically detects the redo gap and resolves it by sending the missing redo to the destination.
          if redo gap is not resolve automatically, then you can use manual method:
          1. copy the log files not yet copied to the standby location
          2.ALTER DATABASE REGISTER LOGFILE 'missing log file path'

          see http://docs.oracle.com/cd/E11882_01/server.112/e10700/log_transport.htm#BABBFCDE

          Tobi
          • 2. Re: gap in archive log
            Shivananda Rao
            Hello,

            The standby database would be out of sync with the primary database if there is a gap of archives that have not been applied to the standby.

            If you have the backup of the missing archives, then you can restore and recover them on the standby database. Suppose, you do not have the backup of the missing archives, then you can go with the roll forward technique to synchronize your standby database with the primary database.

            Take a look at this for going with the roll forward incremental SCN method http://shivanandarao.wordpress.com/2012/03/26/roll-forward-physical-standby-database-using-rman-incremental-backup/

            Hope it helps !!
            • 3. Re: gap in archive log
              abdul:
              hi,
              what happens if there is a gap of 100 archivelogs in between primary and standby database.

              please some one let me know>


              the reaction of this lagging is , standby db goes out of sync means it wud no longer able to apply logs on standby side.
              >
              how to fill that gap?>

              check this link it would clear your doubts:
              http://arup.blogspot.in/2009/12/resolving-gaps-in-data-guard-apply.html
              • 4. Re: gap in archive log
                ozgurumut
                Hi,

                We can say that it is a GAP but firstly you should check some info for solution.

                1. Check Alert Log , because alert.log contains archivelog GAP sequence id.
                2. Check Max Sequence of Archivelog both PROD and Stand By (you've already check )
                select max(sequence#) from v$archived_log where applied='YES';

                If Sequence IDs different you can use many way for solution.
                1. Use RMAN ;

                RESTORE ARCHIVELOG FROM SEQUENCE <GAP min ID> UNTIL SEQUENCE <GAP max ID> ;

                2. You can restore that according to SCN . you can follow this post on below.
                http://emrebaransel.blogspot.com/2008/12/recover-dataguard-from-lost-archivelog.html

                3. Copy Archivelog FTP or SCP It is old way but it is useful sometimes. After this process, you must register Logs.

                4. If Three sections doesn't solve your problem , you can use last and hard method is Full Restore :)

                B.R

                Ozgur