ApsaraDB for RDS offers four editions: Basic Edition, High-availability Edition, Cluster Edition, and Enterprise Edition. This topic describes the Basic Edition.
In the Basic Edition, your database system consists of only one primary RDS instance, and computing is separated from storage. This edition is cost-effective.
- In the Basic Edition, the primary RDS instance does not have a secondary RDS instance as its hot backup. If the primary RDS instance breaks down unexpectedly, is executing specification changes, or is upgrading its version, your database service may be unavailable for a long period of time. If you have high requirements for service availability, we recommend that you select the High-availability, Cluster, or Enterprise Edition. Alternatively, you can upgrade the edition of your RDS instance from Basic to High-availability. For more information, see Upgrade to High-availability Edition.
- A read-only RDS instance that runs the Basic Edition does not provide the service availability that is specified in Alibaba Cloud service level agreement (SLA). Therefore, we recommend that you purchase more than one read-only RDS instance and configure proper read weights for these instances. This allows you to reduce the possibility of service interruptions.
The following figure shows a comparison between the Basic Edition and the High-availability Edition.
The primary RDS instance does not need to replicate data to the secondary RDS instance. Therefore, no extra performance overheads are incurred. This makes the Basic Edition perform better than the High-availability Edition and the Enterprise Edition when the same instance configuration is used.
- Computing is separated from storage. This prevents data losses in the event of failures
on compute nodes.
Note If you set the Backup Frequency parameter to Every 30 Minutes, you can restore data to a point in time within the last 30 minutes in the event of SSD damages or other unexpected failures. This applies only when you are using SQL Server with the Basic Edition. For more information, see Back up an ApsaraDB RDS for SQL Server instance.
- The ultra-large Apsara distributed storage system of Alibaba Cloud is used to store multiple data copies that help ensure reliability.
Only one primary RDS instance is deployed. This reduces your overall costs by 50% compared with the High-availability Edition.
The Basic Edition supports basic features, such as IP address whitelist, monitoring and alerting, and backup and restoration. The Basic Edition does not support the following features:
For more information about the features that are supported by the Basic Edition, see Overview of ApsaraDB for RDS editions.
- Small-sized websites and applications
The Basic Edition is cost-effective and relieves the need for database operations and maintenance (O&M). You can focus only on your business development.
- Personal learning
If you are new to ApsaraDB RDS, you can use the Basic Edition for testing and learning.
- Research and development (R&D)
The Basic Edition allows you to create and release RDS instances anytime and anywhere. This significantly improves R&D efficiency.
Create an RDS instance
For more information about how to create an RDS instance that runs the Basic Edition, see the following topics:
Get started with the Basic Edition
Upgrade to High-availability Edition
- If your RDS instance runs MySQL 5.7, you can upgrade its edition from Basic to High-availability by changing the instance specifications. For more information, see Change the specifications of an ApsaraDB RDS for MySQL instance.
- If your RDS instance runs SQL Server, you can upgrade its edition from Basic to High-availability in the ApsaraDB RDS console. For more information, see Upgrade from Basic Edition to High-availability Edition.
- Why does it take a long time to upgrade the Basic Edition or change the specifications
of my RDS instance?
In the Basic Edition, your database system consists of only one primary RDS instance. When you upgrade the Basic Edition or change the specifications, your database system checks whether the physical server that hosts the primary RDS instance provides sufficient resources. If the physical server does not provide sufficient resources, your database system replicates data to another suitable physical server and switches your database service over to that physical server. This process is time-consuming. In extreme circumstances, your database service may be unavailable for more than 30 minutes. We recommend that you select the High-availability Edition, Enterprise Edition, or Cluster Edition. These editions use the high-availability architecture, which allows you to replicate data from the secondary RDS instance without causing interruptions to your database service. For more information, see High-availability Edition, Enterprise Edition, and Cluster Edition.
- Why does the Basic Edition provide only a small number of features? And which features
are supported by the Basic Edition?
The Basic Edition provides only one primary RDS instance. Therefore, features that are supported by the High-availability Edition, Cluster Edition, and Enterprise Edition are unavailable in the Basic Edition. The Basic Edition is suitable only in a small number of business scenarios. For more information about the features that are supported by the Basic Edition, see the following topics:
Note The Basic Edition is not supported for PPAS or MariaDB.
- Features of ApsaraDB RDS for MySQL
- Features of ApsaraDB RDS for SQL Server
- Features of ApsaraDB RDS for PostgreSQL