6 Replies Latest reply: Jan 30, 2013 12:28 PM by udayjampani RSS

    Archive Log deletion policy for Physical standby

      Hi All,
      Greetings of the day,

      What should be the settings on the physical standby that is running in the Maximum performance mode,inoder to automate ARCHIVE LOG DELETION ON STANDBY

      Mode:Maximum Performance
      Recovery Type:Physical standby

      Current settings:
      1)Running with flash recovery Area
      2)_log_deletion policy =mandatory when checked in x$ksppsv ,x$ksppcv
      CONFIGURE RETENTION POLICY TO REDUNDANCY 1; # default :when checked in rman > show all

      But the archive logs were being deleted manually till now.

      We would like to automate the process of archive log deletion on stand by (only on stand by) .

      1.How to confirm that the current settings were fit for the automatic purging of archival, but never happened , as we are deleting manually and the FRA is not feeling the space pressure.( "FRA will purge only when it feel space pressure ,i.e.85% used")

      2.How can we find the space pressure value ( any parameter or it is defaults to 85).How can we manage the space pressure value i.e reduce 85 value to 50 and see if the automatic purge is happening.As we don't want to take a chance to fill it up to 85.

        • 1. Re: Archive Log deletion policy for Physical standby
          FRA will only deletes the obsolete files if it reaches the threshold limit.

          You are setting the archivelog purge policies in "RMAN", so when you run delete archivelogs command then RMAN will identify which one is applied and not, so based that it will delete the obsolete archivelog files.
          • 2. Re: Archive Log deletion policy for Physical standby
            So, what you mean is
            Whenever we set "CONFIGURE ARCHIVE LOG DELETION POLICY TO APPLIED to standby".

            and running

            delete archivelog all

            On standby ,
            The RMAN will consider only the applied archives for the deletion .Right?

            In that case , what should be the retention policy ( we are not taking any backups at standby).

            • 3. Re: Archive Log deletion policy for Physical standby
              Victor Armbrust
              I used to clean up the archived log files on STANDBY after they are applied.
              To do that i just check it using broker (dgmgrl) and check the lag configuration...

              Another option is to check v$archived_log applied status:
              select * from v$archived_log where APPLIED='YES';
              in both case is manual.

              If you plan to use automatic clean up you should set the threshold for FRA...

              • 4. Re: Archive Log deletion policy for Physical standby

                Also how you set ARCHIVE LOG DELETION POLICY will depend upon where your RMAN backup occurs.

                If you run it on the Standby you might set this to NONE.

                Most of these questions can be answered by reading :

                Using RMAN to Back Up and Restore Files in E25608-04


                Best Regards


                Edited by: mseberg on Jan 30, 2013 12:11 PM
                • 5. Re: Archive Log deletion policy for Physical standby
                  1. What should be the retention policy at standby , if we are not taking backups at stand by,

                  2)What is the effect of logdeletion_policy setting at standby.

                  3) Does the below understanding correct ,
                  CONFIGURE ....applied to standby; is just a setting ,which will make sure that the archive logs that are not applied will not be deleted, and archivelog all will throw errors like "WARNING: archived log not deleted, needed for standby or upstream capture process".

                  CONFIGURE ...applied to standby; cannot make the archives obsolete , the retention policy setting is the only way to do it. If this is the case "when there is space crunch ,will the FRA auto purge process consider the applied archive logs for deletion".How to make them obsolete i.e what is the retention policy that need to be used at standby.

                  • 6. Re: Archive Log deletion policy for Physical standby
                    I read the 11.3 in " http://docs.oracle.com/cd/E11882_01/server.112/e25608/title.htm ".
                    And regarding " 11.3.4 RMAN Configurations at a Standby Where Backups Are Not Performed",

                    We generally don't have any rman scripts / rman cron jobs , where we are not performing any backups , so i thought like it would be automatic archival purge with the setting configure ..... on standby, but is not in real.And that is not mentioned in the document.