RMAN backups
DBAsupport.com Forums - Powered by vBulletin
Results 1 to 8 of 8

Thread: RMAN backups

  1. #1
    Join Date
    Jan 2001
    Posts
    216
    Hi,

    I am working on setting up a backup schedule for our database. We plan to use RMAN and I am looking at incremental backups.

    So, from what I have read so far, we have level 0, 1, 2 and so on. Level 1 backup will backup all changed blocks <= other level 1 backups.

    So, if we schedule say for example, level 0 backup every Sunday, and level 1 backup every other day of the week, and our database was fine for 1 year and then we needed to recover, would we need ALL the level 0 backups from the past whole year and then the level 1 backups for that week when the database went down ?


  2. #2
    Join Date
    Jul 2000
    Posts
    50
    You need the latest one and the incremental backups that are taken after that full backup.

    abhijit

  3. #3
    Join Date
    Oct 2000
    Location
    Saskatoon, SK, Canada
    Posts
    3,925
    You would only require the last Level 0 backup and all the Level 1 backups. On the other hand if you have done a cumulative backup, then you would require the level 0 and the last cumulative of level 1.

    Refer: http://www.oradoc.com/ora816/server....rt1.htm#435958

    Sam
    Thanx
    Sam



    Life is a journey, not a destination!


  4. #4
    Join Date
    Oct 2000
    Location
    Saskatoon, SK, Canada
    Posts
    3,925
    Originally posted by abhijit
    You need the latest one and the incremental backups that are taken after that full backup.

    abhijit
    Remember Full backup is different from the Level 0 backup. Never confuse this, and one will not go with the other.
    Thanx
    Sam



    Life is a journey, not a destination!


  5. #5
    Join Date
    Jan 2001
    Posts
    216
    Thanks for your responses.

    If you look at the following URL

    http://www.oradoc.com/ora816/server....onc.htm#436081

    and search for "Figure 1-14 Differential Incremental Backups (Default)"

    It shows a backup schedule. In there it says that the 0 level backup taken
    on the third Sunday, only backs up till the second sunday and not the first
    sunday.

    Could you please clarify this for me ?

    Thanks again.

  6. #6
    Join Date
    Oct 2000
    Location
    Saskatoon, SK, Canada
    Posts
    3,925
    But if you read the explanation it states what happens:

    An incremental level 0 backup backs up all blocks that have ever been in use in this database.


    Sam

    Thanx
    Sam



    Life is a journey, not a destination!


  7. #7
    Join Date
    Jan 2001
    Posts
    216
    Thanks so much for looking into this. That eases a lot of my concerns, otherwise it will be a nightmare to keep ALL level 0 backups at hand. I guess I was kind of confused when the figure showed something different. Also the definition says "level n backup backs up everything <= n", hence I assumed that level 0 would backup only till the last level 0. But that would be crazy. Hence I think you are right.

    Thanks!

  8. #8
    Join Date
    Oct 2000
    Location
    Saskatoon, SK, Canada
    Posts
    3,925
    That is a general point of confusion for every one.

    Sam
    Thanx
    Sam



    Life is a journey, not a destination!


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


Click Here to Expand Forum to Full Width