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    Disable Oracle Managed Files

    973679
      Hi all,

      I just have a question.

      In my DB I have db_create_file_dest as TRUE parameter (only that one).

      Can I set it as FALSE parameter with alter system set DB_CREATE_FILE_DEST='' scope=both clause without problem?

      I have a pshysical standby in that DB so, have I to change the parameter on Standby instance and rename the Oracle Managed Files labeled datafiles too?

      Thanks a lot.

      Regards!
        • 1. Re: Disable Oracle Managed Files
          JohnWatson
          The parameter does not have a boolean value, it must be set to a directory path.
          • 2. Re: Disable Oracle Managed Files
            973679
            Sorry I think I haven´t explained it so well.

            I know that parameter must have a path in its value, not a boolean one.

            My question is if I can change this parameter with "alter system set DB_CREATE_FILE_DEST='' scope=both" in order to disable Oracle Managed Files on my DB (Primary and Standby) and according to the best practices if I have to rename the OMF's files too.

            Thanks!
            • 3. Re: Disable Oracle Managed Files
              JohnWatson
              I can see no reason why that would cause any problem. Go for it if you want! I don't see the ppoint, though.
              • 4. Re: Disable Oracle Managed Files
                973679
                The problem is Database has seted the parameter in both instances (Primary and Standby) with a directory path, using Oracle Managed Files. The Database is a managed by SAP so when I want to create a new datafile I have to use SAP tool (brtools menu). In the Primary instance, datafiles are created in the path that I've specified discarding OMF parameter, but when the log is shipped to Standby instance, datafiles are created in the OMF path with the proper OMF label.

                As you can see I have datafiles with different name and directory path in Primary and Standby instances so I'm afraid a possible switchover or failover does not work fine.

                This is the reason why I want to disable OMF in both instances and rename the OMF's datafiles in my Standby instance.
                • 5. Re: Disable Oracle Managed Files
                  JohnWatson
                  Oh, I see. Thank you for explaining, it always good to learn something. I can see why you would want the file names to be the same in that circumstance.
                  However, you do not need to worry: Oracle will sort out the file names. Consider that you can use dataguard between a Windows primary and a Linux standby. The names don't matter.
                  • 6. Re: Disable Oracle Managed Files
                    973679
                    So, do you think I don't have to disable OMF and rename the datafiles?

                    I think OMF in SAP environments is not useful because using SAP tools you can create datafiles in the path that you specify. SAP manages Oracle behavior with their own tools.

                    My principal doubt was if I can set to null value the db_create_file_dest parameter on the fly in order to disable OMF.
                    • 7. Re: Disable Oracle Managed Files
                      12cdb
                      Please post OS & DB version.

                      In DG setup if the standby data path and file names are different then you can set a parameter db_file_name_convert on both Primary & Standby

                      http://docs.oracle.com/cd/B19306_01/server.102/b14237/initparams048.htm#CHDEAACI

                      DB_FILE_NAME_CONVERT = 'string1' , 'string2' , 'string3' , 'string4' , ...
                      Where:
                      string1 is the pattern of the primary database filename
                      string2 is the pattern of the standby database filename
                      string3 is the pattern of the primary database filename
                      string4 is the pattern of the standby database filename
                      • 8. Re: Disable Oracle Managed Files
                        973679
                        Hi,

                        SO. AIX 6.1

                        DB Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit

                        I was going to use a manual way to rename the Standby datafiles: Shutdown, mv Unix command and so on.

                        Regards!
                        • 9. Re: Disable Oracle Managed Files
                          12cdb
                          I was going to use a manual way to rename the Standby datafiles: Shutdown, mv Unix command and so on.
                          NO No,

                          You said earlier, "In the Primary instance, datafiles are created in the path that I've specified discarding OMF parameter,"..

                          why did not you specified the same path as Primary when the Standby database was created?

                          I think you can re-configure standby database and move all data files (alter database rename.. ) to the location of your choice followed by setting DB_FILE_NAME_CONVERT on both primary and standby.

                          Also set *.standby_file_management='AUTO'.
                          • 10. Re: Disable Oracle Managed Files
                            973679
                            As I said to John.

                            Primary database is managed by SAP tools and I don't know why OMF is configured. That is the reason why I want to change the paths and names of the Standby datafiles and disable OMF in both servers too in order to matching it with Primary instance, and avoid the mismatching datafiles.
                            • 11. Re: Disable Oracle Managed Files
                              12cdb
                              a bit confusion.

                              if you say,
                              SAP tools and I don't know why OMF is configured
                              Even if the OMF is configured on Primary database, you should be able to change it on Standby database.

                              Why do not you rebuild standby database with new path you like, just make sure you set following two.

                              on Primary =

                              Set DB_FILE_NAME_CONVERT='/OMF LOCATION/', '/LOCATION OF YOUR CHOICE/'
                              Set LOG_FILE_NAME_CONVERT='OMF LOCATION/', '/LOCATION OF YOUR CHOICE/'

                              on Standby
                              Set DB_FILE_NAME_CONVERT='/LOCATION OF YOUR CHOICE/', '/OMF LOCATION/'
                              Set LOG_FILE_NAME_CONVERT='/LOCATION OF YOUR CHOICE/','/OMF LOCATION/'
                              • 12. Re: Disable Oracle Managed Files
                                973679
                                It's rare because only db_create_file_dest is seted, I mean DB_CREATE_ONLINE_LOG_DEST_xx is null in both servers. I supose if I want to use OMF in a better way I have to set both parameters, right? ... so, I prefer using a 'traditional' way to manage the datafiles disabling OMF and matching all the datafiles names and paths.

                                Regards!
                                • 13. Re: Disable Oracle Managed Files
                                  Girish Sharma
                                  As you can see I have datafiles with different name and directory path in Primary and Standby instances so I'm afraid a possible switchover or failover does not work fine.

                                  This is the reason why I want to disable OMF in both instances and rename the OMF's datafiles in my Standby instance.
                                  And what docs are saying :
                                  Oracle recommends that when you set up Oracle Automatic Storage Management (ASM) and Oracle Managed Files (OMF) in a Data Guard configuration, set it up symmetrically on the primary and standby database. That is, if any database in the Data Guard configuration uses ASM, OMF, or both, then every database in the configuration should use ASM, OMF, or both, respectively. See the scenario in Section 13.5 for more information.
                                  http://docs.oracle.com/cd/B28359_01/server.111/b28294/standby.htm

                                  So, there is no issue of using OMF with dataguard, the only thing which you have to remember that it should be everything identical so that the two servers will be easiest to maintain.

                                  Regards
                                  Girish Sharma
                                  • 14. Re: Disable Oracle Managed Files
                                    973679
                                    Girish,

                                    That's my point!! I don't want to use OMF because the DB is managed by SAP, so I want to rename the datafiles in the Standby instace.

                                    Main doubt is if I have to do it using: Shutdown instance, mv Unix command, alter database rename... and so on even if I want to rename System tablespace datafiles.

                                    Thanks a lot!
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