1 Reply Latest reply: Mar 8, 2013 10:15 AM by rcc50886 RSS

    Standby Redo Log

    950800
      Hello everybody,

      I am little novice in Data guard. I have few quesries regarding Standby Redo Log.

      1) My Primary database having 3 online redo log groups and 3 standby redo log groups. My question is during the transaction, will it write in both online redo log and stand by redo log? My guess is NO.

      2) The Standby redolog group on standby recommended to be like : (maximum # of logfiles in primary DB +1) * maximum # of threads on the standby site. If i want to create SRL on the primary, do I have to follow the same recommendation?

      For example: if the primary have 2 groups, the standby should have 3 groups. Do i need to create 3 SRL groups on Primary?

      3) Do we need one additional standby redo log group on the standby database to avoid Primary Database LGWR waiting while redo is applied?

      Thanks in advance
        • 1. Re: Standby Redo Log
          rcc50886
          1) My Primary database having 3 online redo log groups and 3 standby redo log groups. My question is during the transaction, will it write in both online redo log and stand by redo log?
          NO, Standby redo logs will be used only if the database is in standby mode.
          The Standby redolog group on standby recommended to be like : (maximum # of logfiles in primary DB +1) * maximum # of threads on the standby site. If i want to create SRL on the primary, do I have to follow the same recommendation?
          YES, it is recommended to have same number of SRL's created in primary and standby. In case of switch over it makes easy.
          Do we need one additional standby redo log group on the standby database to avoid Primary Database LGWR waiting while redo is applied?
          YES, it is recommended to have additional SRL group.

          -Thanks