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Showing posts from July, 2009

Extract Controlfile from a backupset using RMAN

In my previous post, I had talked about extracting controlfiles, datafiles and archivelogs from RMAN backupsets using the package dbms_backup_restore. In this post, I would like to throw light upon using RMAN as an alternate method that could be employed to extract controlfiles from RMAN backupsets. This method uses the RMAN command "restore controlfile from '<FULL_PATH_TO_CONTROLFILE_BACKUP>'". The RMAN method can be used in 3 scenarios. So, make sure that at least any one of the backups is indeed available. Else, you are DOOMED! I. the controlfile autobackup is turned on in RMAN. In this case the file format would be "c<DBID>-<DATE>-<COUNT>". It is turned on using the command: configure controlfile autobackup on; configure controlfile autobackup format for device type disk to '/opt/apps/vision/backup/%F'; II. the controlfile snapshot backup is configured in RMAN. It is turned on using the command: configure snapshot control

Extract Controlfile, Datafiles & Archivelogs from RMAN Backupsets

The other day, one of my colleagues posed me this interesting and thought-provoking question/scenario: "Suppose, you were to lose both your production and your RMAN catalog databases irrevertably. You do have a full/incremental RMAN backup, however. How are you going to recover?" How indeed? I scratched my head and shone a torch upon the dark recesses of my memory to come up with an answer. The light (of the torch) did indeed reveal something - that is that a note existed in Metalink which list the method that could be used to delve into a RMAN backup set to extract the controlfile, the datafiles and also the archivelogs and Voilà, I hit the nail right on the head. I did some more digging and found a bunch of "Notes" in Metalink that pointed me to the eventual answer to the above question. The Notes that I am referring to are listed below. A summary of the procedure to be followed in such scenarios is also provided. All the notes mentioned use the package dbms_backu

Creating defaultsfile - an easy guide!

This post is for the automation fanatics and enthusiasts. Of course, the others aren't excluded! The defaultsfile option that can be used with adutilities is a handy option to save time during patching or other maintenance activities. Though the defaultsfile gets a mention by almost everyone in the context of reducing downtime, the method of creating it is not, unfortunately. In this post, I'd like to share this using an example - compiling apps schema using adadmin. Note: The full explanation of creating a defaultsfile is mentioned in Chapter 2 (Maintaining Your System) of the Oracle Applications Maintenance Procedures . 1. Run adadmin command as below: adadmin defaultsfile=$APPL_TOP/admin/$TWO_TASK/<DEFAULTS_FILE_NAME> e.g.: adadmin defaultsfile=$APPL_TOP/admin/$TWO_TASK/adadmin_cmpl_apps_schema.txt The above command searches for a file with name adadmin_cmpl_apps_schema.txt in $APPL_TOP/admin/$TWO_TASK directory. If it exists, it uses the values provided in that file.