HP P6000 Replication Solutions Manager Administrator Guide (T3680-96069, June 2012)

In addition to facilitating backup, the replication manager allows you to create instant, independent
copies of one or more database volumes. You can mount these copies on a separate host for batch
processing, data mining, application testing, data warehousing, or other processes that could
benefit from having an independent copy of the database.
For a point-in-time backup to be valid, you must ensure that the replicas contain an
application-consistent copy of the database. Ensure that there are no dirty buffers and that the data
remains valid when the source volume and the replicas are being separated. The replication
manager accomplishes this using the Suspend and Resume job commands.
The Suspend and Resume job commands accept a standard path/file name as input and are
used to execute batch files, scripts, or compiled executables on the specified server at certain points
during execution of the replication manager job. The user must create these files, which execute
a short sequence of specific SQL commands. The examples in this appendix use Oracle
command-line mode to execute short SQL scripts. See the HP P6000 Replication Solutions Manager
User Guide for more information on the Suspend and Resume commands.
The replication manager executes the file in the PRE field before the replica is split from the source
volume. This file should checkpoint the database and place the necessary tablespaces in online
backup mode. The POST file is executed just after the replica is split and is used to take each
tablespace out of online backup mode. If used correctly, the PRE and POST files ensure that the
replica contains a valid and consistent copy of the database.
The Oracle implementation of online or hot backups uses the backup parameter of the alter
tablespace command. For example:
• ALTER TABLESPACE tablespace_name BEGIN BACKUP: Places tablespace_name in
online backup mode.
• ALTER TABLESPACE tablespace_name END BACKUP: Takes tablespace_name out of
online backup mode.
Note that the unit of backup for online backup is the tablespace. To back up an entire database,
you must issue the command for each tablespace. Although online backups target individual
tablespaces, you can back up several tablespaces at once by issuing multiple online backup
commands. HP recommends that you not do this due to undesirable effects of having multiple
tablespaces in online backup mode simultaneously. The replication manager eliminates these
problems by reducing to a few seconds the amount of time that the tablespaces need to be in hot
backup mode.
To use the online backup feature, the database must be operating in ARCHIVELOG mode; otherwise,
online backups will not work.
To enable ARCHIVELOG mode, place the database in the mounted (but not open) state, and then
issue the following commands from the Server Manager prompt:
ALTER DATABASE ARCHIVELOG;ARCHIVE LOG STARTALTER DATABASE OPEN;
To make these changes permanent, you must modify the init.ora file.
Creating a backup plan
A comprehensive Oracle backup plan should include the data files, the archived redo logs, the
control file, and the online redo logs. The Oracle system files should be included as part of the OS
backup.
Data files
Data files are the physical files that contain the tablespace data; they are the most critical
components of any backup. By default, Oracle creates the SYSTEM and USER tablespaces and
their associated data files. In addition to these default data files, each additional tablespace
contains one or more data files. As a database grows, new data files can be added, complicating
the backup plan. To develop an effective backup plan, it is important to understand where each
data file is located and what tablespace it belongs to.
66 Using the replication manager with Oracle tools