Overview

Before connecting to a DB instance, you must create one first. For details about how to create a DB instance, see Buy a DB Instance. You can connect to a DB instance through a private network, Data Admin Service (DAS), or a public network.

**Table 1** RDS connection methods
Connect Through	IP Address	Scenarios	Description
DAS	No IP address is required. You can connect to your DB instance through DAS on the management console.	DAS enables you to manage databases on a web-based console and provides you with database development, O&M, and intelligent diagnosis to make it easy to use and maintain your databases. The permissions required for connecting to DB instances through DAS are enabled by default.	Easy to use, secure, advanced, and intelligent Recommended
Private network	Floating IP	RDS provides a floating IP address by default. When your applications are deployed on an ECS that is in the same region and VPC as RDS, you are advised to use a floating IP address to connect to the RDS DB instance through the ECS.	Secure and high-performance Recommended
Public network	EIP	If you cannot access an RDS DB instance through a floating IP address, bind an EIP to the DB instance and connect the DB instance through the EIP.	Less secure compared with other connection methods To achieve a higher transmission rate and security level, you are advised to migrate your applications to an ECS that is in the same VPC as your RDS DB instance and use a floating IP address to access the DB instance. You need to purchase an EIP. For details, see EIP billing details.

VPC: Virtual Private Cloud
ECS: Elastic Cloud Server
EIP: Elastic IP
You can log in to DB instances using the Data Admin Service (DAS) service or other database clients.
If the ECS is in the same VPC as your RDS DB instance, you do not need to apply for an EIP.

Figure 1 illustrates the connection over a private network or a public network.

Figure 1 DB instance connection
Click to enlarge