• Relational Database Service

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  2. Relational Database Service
  3. User Guide
  4. Getting Started with PostgreSQL
  5. Creating an RDS PostgreSQL DB Instance

Creating an RDS PostgreSQL DB Instance


You can create DB instances using the RDS console or APIs. For details about how to create DB instances using APIs, see the "Creating a DB Instance" section in the Relational Database Service API Reference. This section describes how to create a DB instance on the RDS console.

RDS allows you to tailor your computing resources and storage space to your business needs.


  1. Log in to the management console.
  2. Click in the upper left corner and select a region and a project.
  3. Click Service List. Under Database, click Relational Database Service to go to the RDS console.
  4. On the Instance Management page, click Create DB Instance.
  5. On the displayed page, configure information about the DB instance and click Create Now.

    Table 1 Basic information




    Region in which the tenant is located. Can be changed in the upper left corner of the page.

    DB Instance Name

    Must start with a letter and consist of 4 to 64 characters. It can contain only uppercase letters, lowercase letters, digits, hyphens (-), and underscores (_).

    DB Engine

    Set to PostgreSQL.

    DB Engine Version

    For details, see section DB Engines and Versions.

    Different DB engine versions are supported in different regions.

    You are advised to select the latest available version because it is more stable, reliable, and secure.

    DB Instance Type

    • Primary/Standby: You will have both a primary DB instance and a synchronous standby DB instance. The standby DB instance improves instance reliability and is invisible to you after being created.

      An AZ is a physical region where resources use independent power supply and networks. AZs are physically isolated but interconnected through the internal network.


      Products in different regions cannot communicate with each other through a private network and you cannot change the region of a DB instance after creating the instance. Therefore, exercise caution when selecting a region.

      RDS supports deploying primary and standby DB instances in an AZ or across AZs. You can determine whether the standby AZ is the same as the primary AZ.

      • If they are the same, the primary and standby DB instances are deployed in the same AZ.
      • If they are different (by default), the primary and standby DB instances are deployed in different AZs to ensure failover support and high availability.
    • Single: Only one DB instance is created.

    Time Zone

    Can be selected during DR instance creation and can be changed after the DR instance is created.

    Disk Encryption

    • Disabled: indicates the encryption function is disabled.
    • Enabled: indicates the encryption function is enabled, improving data security but affecting system performance.

      Key Name: indicates the tenant key. You can create or select a key.

      • Once the disk encryption function is enabled, you cannot disable it or change the key after a DB instance is created. Backup data will not be encrypted in OBS.
      • After an RDS DB instance is created, do not disable or delete the key that is being used. Otherwise, RDS will be unavailable and data cannot be restored.
      • For details about how to create a key, see the "Creating a CMK" section in the Data Encryption Workshop User Guide.
    Table 2 Instance specifications



    Instance Class

    Refers to the CPU and memory of a DR instance. Different instance classes refer to different numbers of database connections and maximum IOPS.

    For details about instance classes, see section DB Instance Specifications.

    After a DB instance is created, you can change its CPU and memory. For details, see section Changing the CPU or Memory of a DB Instance.

    Storage Type

    Determines the DB instance read/write speed. The higher the maximum throughput is, the higher the DB instance read/write speed can be.

    • Common I/O: uses the SATA disk type that supports a maximum throughput of 90 MB/s.
    • Ultra-high I/O: uses the SSD disk type that supports a maximum throughput of 350 MB/s.

    Storage Space

    Contains the system overhead required for inode, reserved block, and database operation. Can range in size from 40 GB to 4,000 GB and can be scaled up only by a multiple of 10 GB.

    After a DB instance is created, you can scale up its storage space. For details, see section Scaling Up Storage Space.

    Table 3 Network




    A dedicated virtual network in which your RDS DB instances are located. Isolates networks for different services. You can select an existing VPC or create a VPC. For details on how to create a VPC, see the "Creating a VPC" section in the Virtual Private Cloud User Guide.

    If no VPC is available, RDS allocates a VPC to you by default.


    Improves network security by providing dedicated network resources that are logically isolated from other networks. Subnets take effect only within an AZ. The Dynamic Host Configuration Protocol (DHCP) function must be enabled by default for subnets in which you plan to create RDS DB instances and cannot be disabled.

    Security Group

    Controls the access that traffic has in and out of a DB instance. By default, the security group associated with the DB instance is authorized.

    Enhances security by controlling access to RDS from other services. When you select a security group, you must ensure that it allows the client to access DB instances.

    If no security group is available, RDS allocates a security group to you by default.

    Table 4 Database configuration




    The default login name for the database is root.

    Administrator Password

    Must consist of 8 to 32 characters and must be a combination of uppercase letters, lowercase letters, digits, and at least one of the following special characters: ~!@#%^*-_=+? Enter a strong password and periodically change it to improve security, preventing security risks such as brute force cracking.

    Keep this password secure. The system cannot retrieve it.

    After a DB instance is created, you can reset this password. For details, see section Resetting the Administrator Password.

    Confirm Password

    Must be the same as Administrator Password.

    Parameter Group

    Contains engine configuration values that are applied to one or more DB instances. If you create primary/standby DB instances, they use the same parameter group. After a DB instance is created, you can modify parameters in the parameter group applied to the DB instance.

    For details, see section Modifying Parameters in a Parameter Group.

    Table 5 Tags




    Tags an RDS DB instance. This configuration is optional. Adding tags to RDS DB instances helps you better identify and manage the DB instances. A maximum of 10 tags can be added for each DB instance.

    After a DB instance is created, you can view its tag details on the Tags tab. For details, see section Tags.

    After the configuration, click Price Calculator to view the RDS configuration fee.


    The performance of your DB instance depends on its configurations. Hardware configuration items include the instance specifications, storage type, and storage space.

  6. Confirm the DB instance specifications.

    • If you need to modify your settings, click Previous.
    • If you do not need to modify your settings, click Submit.

  7. To view and manage the DB instance, go to the Instance Management page.

    • Creating a DB instance takes about 15 minutes. During this process, its status is Creating.
    • To refresh the DB instance list, click in the upper right corner of the list. When the creation process is complete, the instance status will change to Available.
    • The automated backup policy is enabled by default. An automated full backup is immediately triggered after a DB instance is created.
    • The default database port number is 5432. After a DB instance is created, you can change the database port.

      For details, see section Changing the Database Port.