6 Replies Latest reply: Feb 6, 2013 9:08 PM by Hemant K Chitale RSS

    RMAN multiple backup schedules

    Simon A
      Hi,

      Version: Oracle Database 11g Release 11.2.0.3.0 Standard Edition
      OS: Red Hat Enterprise Linux Server release 6.3

      I have set up RMAN backups for a database using a full level 0 backupset backup once a week followed by level 1 differential incrementals. These backups are going to the fast recovery area on disk.

      We also have some server backup software which uses RMAN to do backups to tape. The tape backups are also incrementals.

      I am unsure if these backups know about each other. For example, will the 04:00 tape incremental only backup blocks since the previous day 04:00 tape incremental or the same day 01:00 disk incremental?

      If the backups do know about each other is it possible to separate them, so that the tape backups only know about the tape backups.

      Would the best way to be to use Incrementally Updated Backups and the RECOVER COPY OF DATABASE WITH TAG 'incr_update' syntax to apply incremental backups to an image copy? So that the tags are linked.

      Many Thanks for your help.

      Simon
        • 1. Re: RMAN multiple backup schedules
          Mihael
          I have set up RMAN backups for a database using a full level 0 backupset backup once a week followed by level 1 differential incrementals. These backups are going to the fast recovery area on disk.

          We also have some server backup software which uses RMAN to do backups to tape. The tape backups are also incrementals.

          I am unsure if these backups know about each other. For example, will the 04:00 tape incremental only backup blocks since the previous day 04:00 tape incremental or the same day 01:00 disk incremental?
          You should use TAGs to separate backups, otherwise each incremental backup will use latest backup
          Would the best way to be to use Incrementally Updated Backups and the RECOVER COPY OF DATABASE WITH TAG 'incr_update' syntax to apply incremental backups to an image copy?
          yes, but these image copies should be on disk
          • 2. Re: RMAN multiple backup schedules
            Simon A
            Hi,

            So if my disk backups all have the tag 'INCREMENTAL_BACKUP' will the tape backups ignore these? Will the backup with tag 'INCREMENTAL_BACKUP' only backup since the last backup with the same tag?

            If using the below to roll forward the level 0 on disk, does it only use backups with the 'incr_update' tag and ignore the tape backups?

            RUN {
            RECOVER COPY OF DATABASE WITH TAG 'incr_update';
            BACKUP INCREMENTAL LEVEL 1 FOR RECOVER OF COPY WITH TAG 'incr_update'
            DATABASE;
            }

            Many Thanks

            Simon
            • 3. Re: RMAN multiple backup schedules
              Mihael
              So if my disk backups all have the tag 'INCREMENTAL_BACKUP' will the tape backups ignore these? Will the backup with tag 'INCREMENTAL_BACKUP' only backup since the last backup with the same tag?

              If using the below to roll forward the level 0 on disk, does it only use backups with the 'incr_update' tag and ignore the tape backups?

              RUN {
              RECOVER COPY OF DATABASE WITH TAG 'incr_update';
              BACKUP INCREMENTAL LEVEL 1 FOR RECOVER OF COPY WITH TAG 'incr_update'
              DATABASE;
              }
              Yes, with one exception. When you recover image copies, rman will use all available incremental backups.
              • 4. Re: RMAN multiple backup schedules
                Hemant K Chitale
                My guess is that the 04:00 differential incremental backup to tape would backup blocks modified since the 01:00 differential incremental backup to disk.
                That is : the backups are "aware" of each other.

                (how about doing cumulative incrementals ? --- these would always backup all blocks modified since the L0 backup)


                When you issue a RECOVER COPY OF DATABASE WITH TAG 'incr_update' you are applying the incremental backup to the on-disk database copy. The tag of the incremental backup itself is not relevant -- it uses the the tag of the database backup to identify which database backup to update.


                Hemant K Chitale
                • 5. Re: RMAN multiple backup schedules
                  Simon A
                  Hello,

                  Yes, cumulative incrementals might be the best option. So, would the tape incrementals then ignore the disk cumulative backups?

                  After re-reading the documentation I did think that the RECOVER COPY OF DATABASE WITH TAG does not use the tag of the incremental backup. Thanks for confirming.

                  Thanks for the info.

                  Simon
                  • 6. Re: RMAN multiple backup schedules
                    Hemant K Chitale
                    would the tape incrementals then ignore the disk cumulative backups?
                    No. The two backups would be "aware" of each other.


                    Hemant K Chitale