Updated on 2023-12-28 GMT+08:00

DB Instance Introduction

Currently, RDS DB instances are classified into the following types:
  • Single
  • Primary/Standby

Different series support different DB engines and instance specifications.

Table 1 DB instance types

DB Instance Type





Uses a single-node architecture. More cost-effective than the mainstream primary/standby DB instances.

If a fault occurs on a single instance, the instance cannot recover in a timely manner.

  • Personal learning
  • Microsites
  • Development and testing environment of small- and medium-sized enterprises


Uses an HA architecture. A pair of primary and standby DB instances shares the same IP address.

  • When a primary instance is being created, a standby instance is provisioned synchronously to provide data redundancy. The standby instance is invisible to you after being created.
  • If the primary instance fails, a failover occurs, during which database connection is interrupted. If there is a replication delay between the primary and standby instances, the failover takes an extended period of time. The client needs to be able to reconnect to the instance.
  • Production databases of large and medium enterprises
  • Applications for the Internet, Internet of Things (IoT), retail e-commerce sales, logistics, gaming, and other industries