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I've stumped everyone with the previous question about how rman would rather consume infinite disk space than remove obsolete backups. That leads me to this question:

datapump backups work (I have actually tested restoring them), and they are easy to manage unlike rman (if you want to dispute this, answer the previous question!) so why shouldn't I just disable the rman backups and consider that the solution?

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It is not the fault of RMAN if the person using it does not know how to configure the database.

With RMAN you can:

  • restore your database to any point in time in the past that your backups cover, not just the actual state where the backup was created
  • restore large databases significantly faster (have fun with impdp on multi terabyte databases - especially index building and constraint validation, or tens of thousands of partitions, where Data Pump does nothing for hours because it "processes metadata")
  • backup directly to tape/network/whatever through using 3rd party backup solutions (IBM TSM, Networker, Netbackup, Data Protector, etc.)
  • have a central inventory of backups, have automatic deletion based on it
  • compress backups directly without licensing Advanced Compression option (OK, it is not a true technological advantage)

What you can not do with RMAN effectively/easily (but still possible combined with Data Pump), and where Data Pump shines:

  • restore a specific object (table, package, etc.) or a subset of objects
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  • You're listing automatic deletion as a feature of rman, where my previous question was specifically about that not working, and got no answers. I can only conclude that it's something nobody really understands.
    – user41720
    Commented Apr 26, 2017 at 13:40
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    You had control_file_record_keep_time set to 2 and recovery window of 31 days. This is incorrect configuration and this causes the database "forget" about archivelogs and backups, because the database preserves information for 2 days, and reuses the entries in the controlfile that are older than 2 days. Increase control_file_record_keep_time to (recovery window = 31) + (full backup interval) + 1, then in RMAN, run catalog recovery area;. By doing the above, the database will recognize these old files and will be able to delete them according to the used retention policy. Commented Apr 26, 2017 at 13:47
  • @Wumpus Q. Wumbley 7 instead of 2, my bad. Commented Apr 26, 2017 at 14:10
  • catalog recovery area finished with number of files not managed by recovery area is 175, totaling 55.28GB and listed everything in the fast_recovery_area/ARCHIVELOGS. I will transfer this to the other question...
    – user41720
    Commented Apr 26, 2017 at 14:44
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    Actually you do backup with RMAN and other stuff with data pump. :)
    – mutap
    Commented Apr 27, 2017 at 18:53

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