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      • 15. Re: Monthly Backup Plan using Incremental Backups
        user12075536123

        Thank you for advice.


        user472167 wrote
        > First Friday of the month: Full Backup (Incremental Level 0)
        > Monday, Tuesday, Wednesday, Thursday: Incremental Level 1
        > 2nd, 3rd, 4th Friday: Cumulative Incremental Backups Level 1


        I thought it does not backup on Saturday and Sunday.
        It is better to backup archivelog on Friday.


        It corrects as follows.
        ・First Friday of the month                         : backup incremental level 0 database and  backup archivelog all
        ・2nd, 3rd, 4th Friday                                 : backup incremental level 1 database and  backup archivelog all
        ・Monday,Tuesday,Wednesday,Thursday : backup archivelog all

        • 16. Re: Monthly Backup Plan using Incremental Backups
          user472167

          I already answered why I want a monthly cycle.

               "I have to do it this way though because the full database backup is very large and requires a long time to be transferred to the disaster recovery site."

          For this reason I want to transfer the full backup only once in a month. A number of backups are transferred to the DR on the other fridays (2nd-4th) of the month. The first friday of the month is allocated to this oracle system to make a full backup and transfer it to the DR site.

           

          I also answered that I am aware about the extra recovery time and I can easily understand what is the RETENTION PERIOD.

           

          The question is the following:

               According to Doc ID 733535.1 "Realistically a level 2 = a differential level 1."

               In my case though if on the third Friday of the month i execute a cumulative incremental backup level 2, what will the backup contain?

               Will it contain all the differences from second friday (level 1) or from first friday (level 0).


          I only need the answer to this question. I do not care about disk space, recovery time and retention period.

           

          • 17. Re: Monthly Backup Plan using Incremental Backups
            Hemant K Chitale

            >  In my case though if on the third Friday of the month i execute a cumulative incremental backup level 2, what will the backup contain?

            Just write your scripts to use LEVEL 1  backups.  Do not confuse yourself with Level 2.

            I would use CUMULATIVE LEVEL 1 backups on the other Fridays. I would also BACKUP ARCHIVELOG ALL *every* day.

             

            Hemant K Chitale

            • 18. Re: Monthly Backup Plan using Incremental Backups
              user472167

              Come on guys. Can anyone answer the question? What will contain cumulative incremental backup level 2?

              I also know that in case of recovery I will need all the friday backups, all the daily after the last friday and all the archive logs of the last day.

               

              Regarding the archive logs I already said that every 30 minutes the redo log will be archived and backed up.

              • 19. Re: Monthly Backup Plan using Incremental Backups
                Hemant K Chitale

                >What will contain cumulative incremental backup level 2?

                The same as will be contained in a cumulative incremental backup level 1.

                 

                 

                Hemant K Chitale


                • 20. Re: Monthly Backup Plan using Incremental Backups
                  user472167

                  So the conclusion is that cumulative incremental backups of level 2-4=level 1 and that the command allows these levels just for backward compatibility.

                   

                  They should totally remove the support for levels 2-4.  (the Doc ID 733535.1 mentions the word realistically that is confusing)

                  • 21. Re: Monthly Backup Plan using Incremental Backups
                    EdStevens

                    ...user472167 wrote:

                     

                    So the conclusion is that cumulative incremental backups of level 2-4=level 1 and that the command allows these levels just for backward compatibility.

                     

                    They should totally remove the support for levels 2-4.  (the Doc ID 733535.1 mentions the word realistically that is confusing)

                     

                    The reason a lot of syntax (not just here) is kept "for backward compatibility" is not to retain the functionality, but simply to prevent breaking customer's code.  If, as the referenced note indicates, oracle implements an un-documented level 2 as a level 1 differential, then it could legitimately be argued as to whether or not they made a wise choice there.  But that is their decision.  We have to deal with what is. 

                     

                    Now that I understand your reason for the 'monthly' cycle, just be aware that a cumulative incremental can easily grow to be larger than the level 0 backup

                     

                    Day 1 - Level 0 backup -- all populated blocks in the databse

                    Day 2 - Level 1 cumulative -- all blocks changed since day 1 backup

                    Day 3 - Level 1 cumulative -- all blocks changed since day 1 backup

                    Day 4 - Level 1 cumulative -- all blocks changed since day 1 backup

                    Day 5 - Level 1 cumulative -- all blocks changed since day 1 backup

                    ---

                    Day 29 - Level 1 cumulative -- all blocks changed since day 1 backup

                    • 22. Re: Monthly Backup Plan using Incremental Backups
                      user472167

                      I expect that the daily changes would be under 100MB. So on the fourth friday we would have 15 working days * 100MB=1500MB. 1500 would be much less than the full database backup.

                       

                      I remind you the plan I have in mind:

                          First Friday of the month: Full Backup (Incremental Level 0)

                          Monday, Tuesday, Wednesday, Thursday: Incremental Level 1

                          2nd, 3rd, 4th Friday: Cumulative Incremental Backups Level 1

                          Monday - Friday: Every 30 minutes the redo log will be archived and backed up.

                       

                      Will Oracle delete the following backups since the changes will be contained in the next backup?

                      Will they be maintained for point in time recovery?

                         After the n-friday cumulative incremental backup will 29321 delete then n-1 friday cumulative incremental backup? (e.g 3rd friday backup contains the changes of the 2nd friday backup)

                         After the friday backup will Oracle delete all the previous daily incremental backups? (e.g 2nd friday backups contains all the changes recorded on monday-thursday incremental backups after 1st friday full backup)

                      • 23. Re: Monthly Backup Plan using Incremental Backups
                        EdStevens

                        user472167 wrote:

                         

                        I expect that the daily changes would be under 100MB. So on the fourth friday we would have 15 working days * 100MB=1500MB. 1500 would be much less than the full database backup.

                         

                        I remind you the plan I have in mind:

                            First Friday of the month: Full Backup (Incremental Level 0)

                            Monday, Tuesday, Wednesday, Thursday: Incremental Level 1

                            2nd, 3rd, 4th Friday: Cumulative Incremental Backups Level 1

                            Monday - Friday: Every 30 minutes the redo log will be archived and backed up.

                         

                        Will Oracle delete the following backups since the changes will be contained in the next backup?

                        Will they be maintained for point in time recovery?

                           After the n-friday cumulative incremental backup will 29321 delete then n-1 friday cumulative incremental backup? (e.g 3rd friday backup contains the changes of the 2nd friday backup)

                           After the friday backup will Oracle delete all the previous daily incremental backups? (e.g 2nd friday backups contains all the changes recorded on monday-thursday incremental backups after 1st friday full backup)

                         

                        So is your "Monday, Tuesday, Wednesday, Thursday: Incremental Level 1" specified as a differential incremental?

                         

                        I'd have to test the specific scenario (something you could do yourself).  But those "smaller" or "intermediate" incremental would still be needed to enforce recovery window through that time.  If, on Friday you deleted Mon-Thur incremental because you now have a Friday incremental, how would you recover to Thursday afternoon?

                         

                        Maybe I missed it, but I don't recall seeing where you specified if your retention policy is time (days) or redundancy.

                         

                        Since some of your concern seems to be the ability to push a large backup across to a DR site, I'd also consider a couple of other things:

                        1) you don't have to wait until the disaster to push the backups to the site.  Push them over as soon as you make them.

                        2) Data Guard

                        • 24. Re: Monthly Backup Plan using Incremental Backups
                          user472167

                          Yes the daily backups Monday-Thursday will be differential incremental.

                           

                          I will have retention policy of 32 days. A thought I made was if oracle will automatically delete the incremental backups since i will have the archive log backups in case the flash recovery area is close to become full.

                           

                          The backups will be pushed to the DR site as soon as they finish.

                          • 25. Re: Monthly Backup Plan using Incremental Backups
                            EdStevens

                            user472167 wrote:

                             

                            Yes the daily backups Monday-Thursday will be differential incremental.

                             

                            I will have retention policy of 32 days. A thought I made was if oracle will automatically delete the incremental backups since i will have the archive log backups in case the flash recovery area is close to become full.

                             

                            Earlier you had said, "I do not care about disk space,"

                             

                            Are your archivelogs also in the FRA?

                             

                            Again, some specific testing to the specific scenario would be definitive and not at all difficult.  My expectation is rman will not delete anything that can be used to enforce a recovery window.  Yes, you may have archivelogs, but restoring from a backup would be faster than recovering from redo.  If your thinking is that archivlogs can cover it all, why bother with incremental backups at all?

                             

                            The backups will be pushed to the DR site as soon as they finish.

                             

                            Have you considered Data Guard?

                            • 26. Re: Monthly Backup Plan using Incremental Backups
                              user472167

                              That's what I am going to do. I will start with this backup plan and I will check exactly what will Oracle do afterwards. We will have also a backup on tape so there is actually no worry.

                               

                              We have considered data guard but for now it's expensive since we are using standard edition and the total cost would be very high.

                               

                              We are considering a third party tool, dbvisit standby which is much cheaper, however I want a backup plan that will work irrespectively of dbvisit. Anyway if we are going to use dbvisit will be at a later stage.

                               

                              I haven't decided yet if I am going to use FRA for backups and archive logs. Actually for archive logs I think I am going to use FRA because the archive logs will be backed up and deleted every 30 minutes, so there is no worry about disk space. Do you suggest using FRA for backups or an alternative location?

                              • 27. Re: Monthly Backup Plan using Incremental Backups
                                nagulan.selvakumar

                                You can go for manual standby instead of Dataguard as Dataguard can't be used with standard edition. Also manual standby doesn't require additional licence, but just the resource as of your production.

                                 

                                Thank you!!

                                • 28. Re: Monthly Backup Plan using Incremental Backups
                                  user472167

                                  I suspect that this is what dbvisit does in a more automated way.

                                   

                                  Regarding the license we discussed it with Oracle and they said that we need an additional Oracle license for the DR server.

                                  • 29. Re: Monthly Backup Plan using Incremental Backups
                                    EdStevens

                                    user472167 wrote:

                                     

                                    That's what I am going to do. I will start with this backup plan and I will check exactly what will Oracle do afterwards. We will have also a backup on tape so there is actually no worry.

                                     

                                    We have considered data guard but for now it's expensive since we are using standard edition and the total cost would be very high.

                                     

                                    We are considering a third party tool, dbvisit standby which is much cheaper, however I want a backup plan that will work irrespectively of dbvisit. Anyway if we are going to use dbvisit will be at a later stage.

                                     

                                    I haven't decided yet if I am going to use FRA for backups and archive logs. Actually for archive logs I think I am going to use FRA because the archive logs will be backed up and deleted every 30 minutes, so there is no worry about disk space. Do you suggest using FRA for backups or an alternative location?

                                    Yes, I suggest FRA for both backups and archivelogs.

                                    As for deleting the archivelogs (and backups for that matter) be sure you do it ONLY with rman commands.  If you delete them outside of rman -- using simple OS commands to delete files -- rman will have no way of knowing, and will think they are still where they were originally written, and will deduct their size from what it thinks is available in the FRA.

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