This topic describes the limits and usage notes of ApsaraDB RDS.
After you create an RDS instance, you do not need to perform basic database O&M operations, such as high availability configuration and security patching. However, you must take note of the items that are described in the following table.
Item | Description |
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Specification change | When you change the specifications of your RDS instance, ApsaraDB RDS may migrate the data of your RDS instance to a new RDS instance. The incremental data that is generated during the migration process continues to be synchronized to the new RDS instance. After the migration process is complete, ApsaraDB RDS switches your workloads over to the new RDS instance during the switching time that you specify. During the migration process, network interruptions or transient connections may occur. The degree of impact varies across different RDS editions. If network interruptions or transient connections occur, you are unable to perform most of the operations that are related to databases, accounts, and network settings. Important
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Version upgrade | When you upgrade the major engine version or update the minor engine version of your RDS instance, network interruptions or transient connections may occur. The degree of impact varies across different RDS editions. If network interruptions or transient connections occur, you are unable to perform most of the operations that are related to databases, accounts, and network settings. Important
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Failover | RDS High-availability Edition and RDS Enterprise Edition provide a secondary RDS instance that serves as a hot standby. If your primary RDS instance unexpectedly fails, your database system can fail over to the secondary RDS instance within 30 seconds.The period of time that is required for the failover may be longer if data inconsistencies exist between the primary RDS instance or primary node and the secondary RDS instance or secondary node. During the failover process, a transient connection that lasts approximately 30 seconds occurs. We recommend that you configure your application to automatically reconnect to your database system. This prevents interruptions to your workloads. |
Network type change | When you migrate your RDS instance between the classic network and a virtual private cloud (VPC), the server on which your application runs is disconnected from your RDS instance, and a new IP address is assigned to your RDS instance. After the migration process is complete, we recommend that you immediately update the endpoint configuration on your application. |
Data restoration | Before you restore the data of your RDS instance, we recommend that you back up the important data on your RDS instance to prevent data loss. We also recommend that you restore the data of your RDS instance by copying your data to a temporary RDS instance or a cloned RDS instance. After you verify the accuracy of the restored data, you can migrate the data back to your original RDS instance. |
Storage capacity | If the storage capacity of your RDS instance is exhausted, the RDS instance is automatically locked and cannot provide services. We recommend that you check the storage usage on a regular basis. Note If the storage usage is abnormally high, troubleshoot the issue based on the description in What do I do if my ApsaraDB RDS for MySQL instance is locked because its storage capacity is exhausted? |
Performance optimization |
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Limits on database engines