Use DBS to back up an Oracle RAC database - Backup| Alibaba Cloud Documentation Center

Database Backup (DBS) supports backup and restore for Oracle Real Application Clusters (RAC) databases. DBS provides the features of remote backup, long-term archiving, compressed storage, and encryption.

Background information

In an Oracle RAC environment, multiple database instances share the same set of files, including control files, SPFILEs, data files, archived log files, and redo log files. Generally, these files are managed on an Alibaba Cloud Service Mesh (ASM) instance. This ensures that each database instance in the environment can access all the data. Before you back up an Oracle database in an Oracle RAC environment, you must check the locations of the preceding files in the environment and make sure that the files are accessible. For more information, see Query file locations in an Oracle RAC environment.

Features


Feature	Description
Remote backup	DBS supports backup of an Oracle instance to a database on the cloud of another region. DBS allows you to restore the backup data to a standalone instance in a data center or a database on the cloud.
Long-term archiving	DBS can retain your backup data for up to five years. After the five years, DBS automatically transfers the backup set to Archive Storage.
Backup speed limit	DBS allows you to limit the backup speed to reduce the negative impact of backup operations on the database performance.
Compressed storage	DBS supports native compression schemes of Oracle databases and the LZ4 compression algorithm.
Streaming backup	DBS directly writes the backup data to Object Storage Service (OSS) without storing the data on a local disk first.
Encryption	DBS uses HTTPS encryption to transfer data, and AES-256 encryption to store data.

Create a backup schedule

Log on to the DBS console.
On the Backup Schedules page, click Create Schedule in the upper-right corner to go to the DBS buy page.

Set the parameters as described in the following table and click Buy Now.


Section	Parameter	Description
Basic Settings	DBS Region	The region where the DBS instance that you want to purchase resides. Make sure that the selected region is the same as the region where you want to store the backup data.
	Database Type	The type of the database that you want to back up. In this example, select Oracle.
	Specification	The type of the DBS instance that you want to purchase. We recommend that you select xlarge for better performance. For more information, see Select a DBS instance type.
	Backup Method	The mode for backing up data. Valid values: Physical Backup and Logical Backup. In this example, select Physical Backup.
	Storage Size	The storage size of the DBS instance that you want to purchase. You do not need to specify the storage size when you purchase a DBS instance. The storage size is charged in pay-as-you-go mode. You can also purchase a storage plan. A favorable discount is available if you purchase a storage plan with a large size.
Purchase Plan	Quantity	The number of DBS instances that you want to purchase. Set this parameter based on your actual needs.
Purchase Plan	Duration	The validity period of the purchased DBS instance. Set this parameter based on your actual needs.

On the Confirm Order page, confirm your order information, read and agree to DBS Agreement of Service by selecting the check box, and then click Pay.
After you pay for the order, log on to the DBS console and click Backup Schedules in the left-side navigation pane to view the new backup schedule.

Configure the backup schedule

Log on to the DBS console.
In the left-side navigation pane, click Backup Schedules.
On the Backup Schedules page, find the target backup schedule and click Configure Backup Schedule in the Actions column.

In the Configure Backup Source and Destination step of the Configure Backup Schedule wizard, configure the backup source and destination and click Next in the lower-right corner of the page.

Note In this example, the physical backup mode is used. For information about how to back up an Oracle RAC database by using the logical backup mode, see Use DBS to back up an Oracle instance. In this step, you can select a backup gateway that you want to install on the server of an instance in the current Oracle RAC environment and then enter the SID of the Oracle database on this server. This achieves the effect of backing up all the Oracle databases in the current environment.


Section	Parameter	Description
None	Schedule Name	The name of the backup schedule. DBS automatically generates a schedule name. We recommend that you set an informative name for easy identification. You do not need to use a unique schedule name.
Backup Source Information	Backup Mode	The mode for backing up data. By default, the backup mode that you selected when you purchased the DBS instance is used. In this example, the physical backup mode is used.
	Instance Region	The region where the database that you want to back up resides.
	Backup Gateways	The backup gateway that you want to install for backing up data. For more information, see Add a backup gateway. You can install the backup gateway on any of the multiple servers in the current Oracle RAC environment because all the database instances in the environment share the same data.
	Database Type	The type of the database that you want to back up. In this example, this parameter is set to Oracle.
	Whether to back up in the standby database	Specifies whether the database that you want to back up is a primary database or a secondary database.
	Address	The endpoint used to connect to the database that you want to back up. Default value: localhost. This parameter is available only when you set Whether to back up in the standby database to No.
	Port Number	The port used to connect to the database that you want to back up. Default value: 1521. This parameter is available only when you set Whether to back up in the standby database to No.
	SID	The SID of the Oracle database on the server where you want to install the backup gateway. This parameter is available only when you set Whether to back up in the standby database to No.
	Master Address	The endpoint used to connect to the corresponding primary database. This parameter is available only when you set Whether to back up in the standby database to Yes.
	Master Port Number	The port used to connect to the corresponding primary database. This parameter is available only when you set Whether to back up in the standby database to Yes.
	Master SID	The SID of the corresponding primary database. This parameter is available only when you set Whether to back up in the standby database to Yes.
	Standby SID	The SID of the secondary database, namely, the SID of the Oracle database on the server where you want to install the backup gateway. This parameter is available only when you set Whether to back up in the standby database to Yes.
	Master Database Account	The username of the account that you can use to connect to the corresponding primary database. This parameter is available only when you set Whether to back up in the standby database to Yes.
	Master Password	The password of the account that you can use to connect to the corresponding primary database. This parameter is available only when you set Whether to back up in the standby database to Yes.
Backup Destination Information	Backup Storage Type	The type of the storage that you use to back up data. Valid values: DBS built-in storage and OSS for user.
	OSS Bucket Name	The name of the OSS bucket. This parameter is available only when you set Backup Storage Type to OSS for user.
	Storage Encryption	The method that you use to encrypt the stored data. Valid values: Non-encrypted, Encrypted, and KMS Encrypted.

In the Edit Backup Objects step, Back Up Entire Instance is automatically selected. Click Next.

Note If you back up an entire database, permission data and stored procedures are also backed up.

In the Configure Backup Time step, set the parameters as described in the following table and click Next.


Parameter	Description
Full-scale Backup Frequency	The frequency of the backup schedule. Valid values: Periodic Backup and Single Backup.
Full Data Backup Recurrence	The day in a week on which DBS runs the backup schedule.
Full Data Backup Start At	The start time of the backup. If the time taken for a full data backup is longer than the backup interval, DBS skips the next backup.
Real-Time Transaction Log Backup	Specifies whether to enable incremental backup.
Maximum Concurrent Threads for Full Data Backup	The maximum number of concurrent threads available for a full data backup. The value varies with the specifications of the DBS instance that you purchased when you created the backup schedule.
Transaction Log backup interval	The interval at which incremental backup is performed.
Does not automatically delete backed up incremental	Specifies whether to automatically delete historical incremental backups.
Enable compression	Specifies whether to enable compression.
Backup set mode	The backup mode for backing up the database. If you select Non-intrusive streaming backup, DBS uses the Oracle System Backup to Tape (SBT) interface to back up data. Backup data is stored as backup sets on a virtual tape before the data is streamed to the cloud. This method uses less storage space and does not have a negative impact on the source database. If you select Mount backup in seconds, DBS uses disks to back up data. Backup data is stored as backup sets on a virtual disk before the data is streamed to the cloud. This method allows you to restore data in seconds and does not have a negative impact on the source database.

In the Edit Lifecycle step, configure the lifecycle for a full data backup in the Configure Full Data Backup Lifecycle section and the lifecycle for an incremental data backup in the Configure Transaction Log Backup Lifecycle section.
After the configuration is complete, click Precheck in the lower-right corner of the page.
If the Precheck Passed message appears, click Start Task.

Note When the status of the backup schedule changes to Running, the backup schedule takes effect.

View the backup schedule

Log on to the DBS console.
In the left-side navigation pane, click Backup Schedules.
On the Backup Schedules page, find the target backup schedule and click Manage in the Actions column.
The Configure Task page displays the basic information and running status of the backup schedule.
In the left-side navigation pane, choose Backup Tasks > Full Data to view information about all full data backups. To view information about all incremental data backups, choose Backup Tasks > Transaction Log Backup.

Restore an Oracle RAC database

Log on to the DBS console.
In the left-side navigation pane, click Backup Schedules.
On the Backup Schedules page, find the target backup schedule and click Manage in the Actions column.
On the Configure Task page, click Restore Database in the upper-right corner.

In the Set Time Restored To step of the Create Restore Task wizard, set the parameters as described in the following table and click Next.


Section	Parameter	Description
None	Task Name	The name of the restore task. DBS automatically generates a task name. We recommend that you set an informative name for easy identification. You do not need to use a unique task name.
Set Time Restored To	Time Range Available to Restore	The time range available for restoring backup sets. DBS automatically displays the available time range.
Set Time Restored To	Restore To	The point in time that you want to restore the source database to. The value must be within the time range that is specified by the Time Range Available to Restore parameter.
Configure Destination Database	Instance Region	The region where you want to install a backup gateway for restoring data.
	Backup Gateways	The backup gateway that you want to install for restoring data. For more information, see Add a backup gateway. You cannot restore data to the same sever where data is backed up. Therefore, you cannot install the backup gateway for restoring data on the same server where the backup gateway for backing up data is installed.
	Database Type	The type of the database that you want to restore. In this example, this parameter is set to Oracle.
	Address	The endpoint used to connect to the database that you want to restore. Default value: localhost.
	Port Number	The port used to connect to the database that you want to restore. Default value: 1521.
	SID	The SID of the database that you want to restore.
	Destination Directory	The directory used to restore the database.
	Database program directory	The program directory of the restored database. In this example, set this parameter to the absolute path that is specified by the ORACLE_HOME variable.

In the Configure Objects to Restore step, set Restore Mode to Restore Entire Instance and click Precheck.
If the Precheck Passed message appears, click Start Task.

Note You can restore an Oracle RAC database only to a standalone database instance, not an Oracle RAC database.

Query file locations in an Oracle RAC environment

To query locations of redo log files, execute the following SQL statement:
```
select member from v$logfile where type='ONLINE';
```
The following figure shows a response. Each MEMBER entry starts with +. DBSBAKDAT1DG indicates the name of the ASM instance that is used to manage the files in the current Oracle RAC environment.
To query locations of archived log files, execute the following SQL statement:
```
select name from v$archived_log where DELETED='NO';
```
The following figure shows a response.Each NAME entry starts with +. DBSBAKDAT1DG indicates the name of the ASM instance that is used to manage the files in the current Oracle RAC environment.
To query locations of data files, execute the following SQL statement:
```
select name from v$datafile;
```
The following figure shows a response. Each VALUE entry starts with +. DBSBAKDAT1DG indicates the name of the ASM instance that is used to manage the files in the current Oracle RAC environment.
To query locations of SPFILEs, execute the following SQL statement:
```
show parameter spfile;
```
The following figure shows a response. Each VALUE entry starts with +. DBSBAKDAT1DG indicates the name of the ASM instance that is used to manage the files in the current Oracle RAC environment.
To query locations of control files, execute the following SQL statement:
```
select member from v$logfile where type='ONLINE';
```
The following figure shows a response.Each VALUE entry starts with +. DBSBAKDAT1DG indicates the name of the ASM instance that is used to manage the files in the current Oracle RAC environment.