8 Replies Latest reply: Feb 6, 2013 11:20 PM by Mihael RSS

    Backup Strategy For Large Database

    user11982706
      Hi all,


      In my current setup I am having luxury of having very less load on database on weekend’s with very few users and database size is around 500G.
      We use to take Level 0 backup every weekend and daily Level 1 backups. During backups performance of our database degrades but it’s fine as
      Number of users is very less to notice that.

      Now, in an situation where DB is in use 24 * 7 and size in few TB’s then how to plan for backup’s. I mean every weekend level 0 won’t be possible
      Where there are good number of users or where there is business lose due to slow performance. What would be the RMAN backup Strategy
        • 1. Re: Backup Strategy For Large Database
          mseberg
          Hello;

          Would consider something like this :

          Sunday Level 0
          Monday Incremental 1
          Tuesday Incremental 1
          Wednesday Cumulative Incremental
          Thursday Incremental 1
          Friday Incremental 1
          Saturday Incremental 1

          You have do a Level 0 every now and then because the Incremental 1's are worthless without it. You could go every other weekend if you had to, but I would avoid if possible.

          The other option is Data Guard and off load the backup to the Standby.

          Best Regards

          mseberg
          • 2. Re: Backup Strategy For Large Database
            Shivananda Rao
            Hello,

            No matter what the database size is, backing it up is prioritized. Only thing that can help out is carrying out the L0 backup when the load is less (during business off hours). You can take L0 backup on Sundays and L1 backups on the remaining days.


            Regards,
            Shivananda
            • 3. Re: Backup Strategy For Large Database
              Mihael
              Now, in an situation where DB is in use 24 * 7 and size in few TB’s then how to plan for backup’s. I mean every weekend level 0 won’t be possible
              Where there are good number of users or where there is business lose due to slow performance. What would be the RMAN backup Strategy
              You can use rman feature to roll forward image copies. In this case you need to perform level 0 database backup only once.
              • 4. Re: Backup Strategy For Large Database
                Seberg
                In which case you only have one copy of the backup or all your eggs in one basket as they say.
                • 5. Re: Backup Strategy For Large Database
                  user11982706
                  does a tablespace level bacup depends upon a level 0 backup ?

                  I mean, if i take a tablepsace level backup on Monday and on tuesday if i have to recover that tablespace, will it be possible to restore that tablespace from Monday's backup and apply archives generated till now for that particular tablespace ?
                  • 6. Re: Backup Strategy For Large Database
                    mseberg
                    Hello again;

                    If you are talking about tablespace point in time recovery beware you cannot recover from a dropped tablespace.

                    TSPITR does not depend upon a full but has several limits.

                    http://docs.oracle.com/cd/E14072_01/backup.112/e10642/rcmtspit.htm

                    Correction

                    You want to recover dropped tablespaces. In fact, RMAN can perform TSPITR on dropped tablespaces even when a recovery catalog is not used.

                    This is starting to show some age, but worth a look :

                    http://asktom.oracle.com/pls/asktom/f?p=100:11:0::::P11_QUESTION_ID:656444800346932623

                    You may have already seen this one : ( Backing Up and Recovering VLDBs )

                    http://docs.oracle.com/cd/B28359_01/server.111/b32024/vldb_backup.htm



                    Best Regards

                    mseberg

                    Edited by: mseberg on Feb 6, 2013 1:52 PM

                    Edited by: mseberg on Feb 6, 2013 1:58 PM
                    • 7. Re: Backup Strategy For Large Database
                      Hemant K Chitale
                      and apply archives generated till now for that particular tablespace ?
                      As you are doing "complete" recovery to the current point in time .... yes you can use such tablespace backups.

                      In fact, tablespace backups is also a strategy when dealing with large databases.

                      Say you have 5 tablespaces.
                      Each week day you run a separate Tablespace backup.
                      On Sunday, if you can, you run a full database backup. If you do not have time for full database backups on Sunday, you stick to Tablespace backups such that the gap between two backups of the tablespace is not very large (e.g. a week).
                      Of course, you must consider the ArchiveLogs and ensure that you have multiple (separate Tapes) backups of ArchiveLogs (you don't want a tape error on restore of archivelogs to prevent you from recovering a tablespace !).


                      Hemant K Chitale
                      • 8. Re: Backup Strategy For Large Database
                        Mihael
                        In which case you only have one copy of the backup or all your eggs in one basket as they say.
                        No. You can have many levels 0 updatable backups.