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					                                        TABLE OF CONTENTS
1.1 BACKUP MODES.................................................................................................................................. 2
    1.1.1 OFFLINE.............................................................................................................................................. 2
    1.1.2 ONLINE ............................................................................................................................................... 2
1.2 OFFLINE VS ONLINE.......................................................................................................................... 2
    1.2.1 OFFLINE.............................................................................................................................................. 2
    1.2.2 ONLINE ............................................................................................................................................... 3
1.3 OFFLINE BACKUP USING NT BACKUP ......................................................................................... 3

2.1 SAP BACKUP UTILITIES ................................................................................................................... 5

3.1 BACKUP METHODS AND BACKUP FREQUENCY ...................................................................... 5
    3.1.1 BACKING UP COMPLETE DATABASE .................................................................................................... 5
    3.1.2 BACKING UP A TABLESPACE ............................................................................................................... 6
    3.1.3 BACKING UP A CONTROL FILE ............................................................................................................ 6
    3.1.4 BACKING UP THE ARCHIVE FILES........................................................................................................ 7
3.2 BACKING UP TO DISK, THEN TO TAPE ........................................................................................ 7

3.3 EXPORT AND IMPORT ...................................................................................................................... 7
4     RECOMMENDED BACKUP SCHEDULE FOR PIFRA...................................................................8
Backup Strategy
By Backup we mean to make copies of files from one destination to another. Both, the
source destination and the target destination can be on the same or on different storage
device. You can restore your data from the backup if the original files are damaged or
lost.

1.1 Backup Modes
There are two types of backup.

      Offline
      Online
1.1.1 Offline

Offline backup is taken with the database stopped - that is, the users cannot work.

In an offline backup of the complete database, you have a backup of the database that is
consistent. If you work with the database after the backup, the backup is consistent, but
not up-to-date. In this case, you have to recover the database after you restore the
backup.
1.1.2 Online

Online backup is taken with the database running - that is, the users can continue to
work normally. The management of database changes by the corresponding Oracle
background processes is not affected either.

1.2 Offline Vs Online

1.2.1 Offline

An offline backup is taken with the Oracle database and SAP R/3 System down (that is,
not running).

Benefits:
       An offline backup is faster than an online backup.
      There is no issue with data changing in the database during the backup.
      Related operating system level files will be in sync with the R/3 database, if they
       are backed up at the same time.

Disadvantages:
       R/3 is normally not available for use during an offline backup. If the “split mirror”
       technique is used, the database will be shutdown for a short time, while R/3
       continues to run.
       Buffers for R/3 and database are flushed. This will impact performance until the
       buffers are populated.
1.2.2 Online

An online backup is taken with both the Oracle database and SAP R/3 running.

Benefits:
       SAP R/3 is available to users during backup.
Having a system that is available 24-hours a day may be critical in manufacturing or
other areas where the system provides information to global users.

      Buffers are not flushed.
Since buffers are not flushed, there is no impact to performance once the backup is
complete.

Disadvantages:
      An online backup is somewhat slower than an offline backup, resulting in a
       longer backup time. Backup time is increased because processes such as SAP
       R/3 are running and competing for system resources.
      Online performance is degraded while the backup is running.
      Data may change in the database while it is being backed up. Because of this,
       the redo logs become critical to a successful recovery.
      Related operating system level files may be out of sync with the R/3 database.

1.3 Offline backup using Operating System Backup Utility
The offline backup is done when SAP R/3 and the database are down. Here, we also
use the offline backup to also backup other files which are needed to restore SAP R/3.
Since high capacity tape drives are now more common, it is simple and safe to backup
the entire server. This full server backup eliminates the possibility of not backing up an
important file.

The data in the database does not change while the backup is being made, which
means that you have a static “picture” of the database and do not have to deal with the
issue of data changing while the backup is being run. With some third party applications,
you cannot back up the files unless they are closed, and this is not possible unless R/3
and the application are shut down. Therefore, an offline backup needs to be done. A “full
server” offline backup also gives you the most complete backup in the event of a
catastrophic disaster. On one tape, you have everything on the server.


Data to be backup
Offline backup:
     Operating system executable files.
     Program files.
     Oracle executable files.
     Oracle Data files.
     Original and mirror log files.
     Control files.
    Sap executable files.
Online backup:
    Oracle Data files.
    Original and mirror log files.
    Control files
    Offline Redo log files.
2.1 SAP Backup Utilities
SAP offers the utility programs BRBACKUP, BRARCHIVE and BRRESTORE. Use these
programs to realize the recommended backup concepts. Each of these programs has its
own range of functions (backup, archiving the redo log files, restore). In addition, the BR
programs also have their own utility programs, BRCONNECT and BRTOOLS. These are
not called by the database user, the BR programs call them themselves for a particular
task.




3.1 Backup methods and Backup frequency

3.1.1 Backing up complete database

      The frequency of image backups of the entire database should depend on the
       degree of activity in your database system. High activity in the database
       increases the number of redo log files written between complete backups. This
       increases the time required for any necessary recovery.

      The safety level of your database operations is increased the more often you run
       backups. If a redo log file is lost, complete recovery of the database after an error
       is often not possible. Instead, you will only be able to recover up to the gap in the
       redo log file sequence.
      Performing frequent complete backups reduces the number of redo log files
       which must exist in order to make a complete recovery. The data loss should one
       of these files be lost can thus be kept to a minimum.

      To perform an online backup, the database must be in ARCHIVELOG mode; production
       operations can then be continued without restrictions, unlike and offline backup.

      SAP recommends keeping several generations of complete backups and the
       corresponding redo log files. This ensures that you can still recover the database,
       even if the last complete backup is lost.

      To enable fast, simple recovery of the database, back up at least the changed
       tablespaces and the control file after every structure change (new, changed, or
       deleted tablespaces; new data files). After reorganization with data files, always
       back up the affected tablespace if you want to use the recovery functions of
       SAPDBA. Follow the instructions for the tablespace backup below.

      Use the SAP utility BRBACKUP to back up the database and BRARCHIVE to
       archive the offline redo log files
3.1.2 Backing up a Tablespace

Backing up tablespaces that are changed frequently can reduce the time required for
any necessary recovery. When a more recent backup of an intensively used tablespace
is available, fewer redo log entries will have to be processed in order to update the
tablespace. If you are able to back up the entire database on a daily basis, tablespace
backups are not necessary.

Note that tablespace backups are no replacement for frequent backups of the entire
database.

      If you only perform tablespace backups for a long period of time, this increases
       your dependence on the archived redo log files, and therefore the risk of data
       loss if one of the redo log files is lost.

      If tablespace backups are used, the database administrator decides what has to
       be backed up. The SAP utility BRBACKUP supports the backup operation itself,
       but does not help you decide which tablespaces to back up (exceptions:
       operations such as a tablespace extension, or SAPDBA reorganization; in these
       situations, SAPDBA recommends that you backup the tablespace immediately).

3.1.3 Backing up a Control file

Another type of partial backup is to back up the control file. The control file records the
physical file structure of the corresponding database. You should therefore back up the
control file after every structure change.

Mirrored control files protect you against the loss of a single control file. If data files are
damaged, an older control file that mirrors the corresponding structure of the database
may be necessary for recovery. For this reason, mirroring the control files is by no
means a replacement for backing up the control file after every change in the structure of
the database.
When the SAP utility BRBACKUP is used to back up the database files, the control file is
always saved along with them. The control file is saved before and after the operation for
various administration measures with SAPDBA (for example, tablespace extension, and
reorganization of a tablespace).
3.1.4 Backing up the Archive files

The archive files should be backed up regularly so as to in case of any instance or
media failure, the database can be restored and recovered with the help of archive
backup set.

In case of point in time recovery or incomplete recovery, the archives are the only files
available which can be use to bring back the database consistent.

The archive files are used in different types of incomplete recoveries.
3.2 Backing up to disk, then to Tape
Advantages:
              For the database, this option is the fastest. Under most situations, you
               can back up to disk faster than to tape.
              This option allows you to make several identical backup copies (for
               example, one for onsite storage and one for offsite storage).
              Once the backup has been made to disk, R/3 System performance is
               minimally affected. Because the tape backup is made from the disk copy,
               and not the live database, the backup to tape is not competing with
               database activity for significant system resources.
              During an onsite disaster recovery to the same equipment, the recovery
               can be done from the on-disk backup.
Disadvantages:
              Significant additional disk space, up to the same amount of space as the
               database, is required. This additional space makes this option the most
               expensive, especially for a large database.
              Until the backup to tape is completed, you are vulnerable to a data center
               disaster.
3.3 Export and Import
The dump files created by the export can also be used for recovery. The advantage of
this method is that a single object or a client can also be restored through import
process.
4. Recommended Backup Schedule for PIFRA
The recommended and followed backup strategy at PIFRA for the Development
System, Quality Assurance System and the Production System(s) is as follows:



DAYS                                BACKUP METHOD

Monday                              Online Database backup

Tuesday                             Online Database backup

Wednesday                           Online Database backup

Thursday                            Online Database backup

Friday                              Online Database backup

Saturday                            Full offline (OS LEVEL)

				
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