Question Re: Oracle Db backup type - DB13 in Technology Q&A

Oracle Db backup type - DB13

former_member189462 — Sat, 05 May 2012 14:49:13 GMT

Hi All,

System Data:

Oracle 10g

Windows Server 2008

I would like to ask for your recommendation with regards to the backup type to use considering a future recovery needs. This is the scenario: We have just installed an ERP IDES version system (there has been no activity on it yet, no released to user neither). So we want to perform a DB backup to a local disk before start using it and when requires, to have the chance to go back to this point. Considering that requirement what would be the more suitable backup type option available in DB13?

-Full DataBase Onlie Backup

-Full DataBase Offline Backup

-Whole DataBase Offline Backup

-Whole DataBase Online Backup

I'm aware about the advantages and disadvantages between online vs offline, but I'm not sure about differences between "Whole" and "Full" and the requirements of them for the recovery.

Summarizing...What would be the right procedure to have a DB backup to use it later for recovery?

Also and considering the backup device type is a Disk I've have already change backup_dev_type=disk parameter in init<SID>.sap file. Should I change other parameters like backup_mode or backup_type for example?

As you can see I'm new on this Oracle "backup/restore" procedures.

Thanks and regards

Re: Oracle Db backup type - DB13

Former Member — Sat, 05 May 2012 18:48:40 GMT

Hi Diego.

Different between Whole backup & Full backup

Whole backup

Backup all database files,but this backup are not cataloged as a level-0 backup, which means that you cannot use it as a reference backup for an incremental backup with RMAN .

The syntax for a whole backup is as follows : In Profile init<DBSID>.sap :backup_mode=all

BRBACKUP brbackup -m all

Full backup

backups all database files. you can preform a full backup with or without RMAN . if you do not use RMAN ,then RMAN is called separately to catalog the backup as level 0. This means that you can use this backup as a reference backup for an incremental backup with RMAN .

The syntax for a Full backup is :

In profile init<DBSID>.sap : backup_mode=full
With BRBACKUP : brbackup -m full

In the context of the Recovery Manager this backup is an incremental level-0 backup.

RMAN is proprietary tool of Oracle which checks the consistency of the backup where as brbackup does not checks the consistency

Re: Oracle Db backup type - DB13

former_member189462 — Sun, 06 May 2012 14:42:58 GMT

Hi Tunga, thanks for the quick response

Considering the above mentioned differences between whole and full backups, and considering also I'm new on this, Could you please let me know the steps to perform a full online db backup to a Disk through the Tx DB13? What parameters should be modified init<SID>.sap besides backup_dev_type?

Regards

Re: Oracle Db backup type - DB13

former_member189462 — Mon, 07 May 2012 03:02:31 GMT

Hi,

Finally I've successfully performed an online backup through BRTOOLS, with following parameters in init<sid>.sap file.

backup_mode= full
backup_type= online
backup_dev_type= disk
backup_root_dir= D:\oracle\<SID>\sapbackup

After checking the backup result, the following structure and files were found in the above backup directory:

Directories:

<SID>:

      back<SID>.txt
      beimhhyn.Saved Search
      initSID.ora
      initSID.sap
      spaceSID.txt
      SPFILESID.ora

beimhhyn:
      CNTRL<SID>.DBF
      SR3.DATAx (x=70)
      SR3USR.DATA1
      SYSAUX.DATA1
      SR3701.DATAx (x=69)
      SYSTEM.DATA1
      UNDO.DATA1

Are all these backup files sufficient to perform a restore? Or some other files are also required? Basically I would to confirm if by keeping all the above listed files we are in position to restore the system and bring it to its today state.

Thanks and regards

Re: Oracle Db backup type - DB13

Former Member — Mon, 07 May 2012 11:22:18 GMT

Hi Diego,

You should take online consistent backup which contains datafiles and offline redo log files, in order to open the database, as a minimum requirement. You may not open the database consistently, only with online backup.

In order to bring the database to its today state, you need take a online backup, as you did, plus should all take backup offline redolog files periodically, in the day.

Assume that the online backup finished at t1 and the database crashed at t2. To bring the database to t2, you need to restore the online backup which will bring you to t1. Then, apply the offline redolog files which will bring your database to t2 or the time between t1 and t2.

Best regards,

Orkun Gedik

Re: Oracle Db backup type - DB13

former_member189462 — Mon, 07 May 2012 12:34:54 GMT

Hi Orkun, thanks for your response

Considering we have not yet released the system to users (no activity over it) and this backup will be only used to bring the system to time "t1" (no need to reach an specific hour in that process)...Is this online backup sufficient for this?

An extra question..Is there any way to check if this backup is consistent or usable without really performing the restore process?

Regards and sorry for this kind of questions.

Thanks

Re: Oracle Db backup type - DB13

Former Member — Mon, 07 May 2012 12:51:05 GMT

Hi,

>> Considering we have not yet released the system to users (no activity over it) and this backup will be only used to bring the system to time "t1" (no need to reach an specific hour in that process)...Is this online backup sufficient for this?

If there's no activity and able to stop the system for a while take an offline backup, instead of online backup. This is because, by the offline backup you don't need to apply offline redologs in order to make the database consistent. If it is not possible to shutdown the system, I suggest you to take an online consistent backup. Just online may not be enough to open the database.

>> Is there any way to check if this backup is consistent or usable without really performing the restore process?

You need to restore the backup set, in order to be sure that it is working

Best regards,

Orkun Gedik

Re: Oracle Db backup type - DB13

former_member189462 — Mon, 07 May 2012 14:45:02 GMT

Hi Orkun,

I'm able to stop the system. So...I'll proceed with your recommendation of an offline backup option. Just to be sure everything is right...Could you please confirm if the following parameters in init<SID>.sap file are correct?

backup_mode= full

backup_type= offline
backup_dev_type= disk
backup_root_dir= D:\oracle\<SID>\sapbackup

Thanks so much for your help

Regards

Re: Oracle Db backup type - DB13

Former Member — Mon, 07 May 2012 14:56:57 GMT

Yes, the configuration is correct. Additionally, don't forget to set expiration period to the suitable number with your needs, if you are planning to make a backup cycle.

expir_period = 30

Best regards,

Orkun Gedik

Re: Oracle Db backup type - DB13

former_member189462 — Mon, 07 May 2012 15:36:49 GMT

Hi Orkun...thanks so much for your help. I'll try it and let you know.

Regards