Create Standby Database (step 4) – Linux/Unix
This step can be skipped, if a standby database is already present. Dbvisit Standby can work with existing standby databases. Dbvisit Standby will automatically register the existing standby database. Dbvisit Standby does not distinguish between an existing standby database and a standby database created through Dbvisit Standby.
Dbvisit Standby can automatically create the standby database. The standby database will reside on the standby server and is an exact binary copy of the primary database.
The standby database only needs to be created once. After the standby database is created, Dbvisit Standby will automatically ensure the standby database is kept up to date with the primary database.
Dbvisit Standby normally uses the network to transfer the primary database to the standby server to create the standby database. For slow networks or very large databases, use the transportable media creation method to create the standby database.
The primary database will not be shutdown during standby database creation. Dbvisit Standby uses RMAN in most cases to make a backup of the primary database.
Perquisites for creating the standby database are:
- Oracle software must be installed on the standby server.
- Enough free space on the standby server must be available for the standby database.
- The Oracle background (cdump, udump, bdump etc ) and admin directories are created. These directories can be created by Dbvisit Standby if you choose the option to create missing filesystem directories automatically
Dbvisit Standby allows the following options for creating the standby database:
- Regular file system standby database with
i) Same structure as primary database or,
ii) Different structure as primary database.
- ASM standby database (for Oracle version 10.2 and higher) with
i) Same structure as primary database or
ii) Different structure as primary database.
If the new standby database has FRA enabled, please remove all files from FRA/<unique_db_name> folder on the standby server, prior to creating the database. This is to avoid resetting the standby database incarnation triggered by the presence of old database files in FRA.
Dbvisit Standby - standby database creation methods:
The following methods are available to create the standby database:
- Direct transfer to the standby server (on the fly creation) over the network.
- Using a temporary location to create a complete backup of the primary database and then transferring the complete backup from the temporary location on the primary server to the standby server over the network.
- Transportable Media which uses a temporary location to create a complete backup of the primary database and manually transferring the complete backup to the standby server using TRANSPORTABLE MEDIA. Transportable media is an external device such as a USB drive that is first plugged into the primary server and then manually transferred to the standby site and plugged into the standby server to complete the process.
Option 1 should be chosen for smaller databases.
Option 2 should be chosen for larger databases.
Option 3 should be chosen for very large databases or slow networks.
Option 2 and 3 will require adequate space on the primary server to make a (compressed) copy of the database files.
Standby database spfile/pfile
The spfile.ora (pfile.ora for Oracle database version less than 9) is created for the standby database using the init.ora or spfile.ora file from the primary database. Oracle database parameters for the standby database can be customised. If an existing init.ora or spfile.ora file is already present on the standby server, it will be overwritten.The Create Standby Database wizard will guide the process for customizing of the Oracle standby database during the creation process. The settings can be saved as a template for future use. If a standby database template has been created previously, this can be used to create the standby database. No further questions will be asked.
For more information about creation of standby database, please see Creating Standby Databases automatically with Dbvisit Standby.