Updated on 2024-10-30 GMT+08:00

Buying and Connecting to an Instance

This section instructs you to buy a GeminiDB Cassandra instance on the GeminiDB console.

By default, each tenant can have 50 GeminiDB Cassandra instances. To request a higher quota, contact customer service.

Prerequisites

  • You have created a Huawei Cloud account.

Step 1: Buying an Instance

For details, see Buying an Instance.

  1. Log in to the GeminiDB console.
  2. In the service list, choose Databases > GeminiDB Cassandra API.
  3. On the Instances page, click Buy DB Instance.
  4. On the displayed page, select a billing mode, configure instance parameters, and click Next.
    The following parameters are for reference only. Select proper specifications as needed. Table 1 lists details about the parameters.
    Figure 1 Billing mode and basic information

    Parameter

    Example Value

    Description

    Billing Mode

    Pay-per-use

    Billing mode of an instance

    • Yearly/Monthly: A prepaid billing mode in which you pay for resources before using it. Bills are settled based on the subscription period. The longer the subscription term, the bigger the discount. This mode is a good option for long-term stable services.
    • Pay-per-use: A postpaid billing mode. Pay as you go and just pay for what you use. The DB instance usage is calculated by the second but billed every hour. This mode allows you to adjust resource usage easily. You neither need to prepare for resources in advance, nor end up with excessive or insufficient preset resources.

    Region

    Select CN-Hong Kong.

    Region where a tenant is located

    NOTICE:

    Select the region nearest where you will access the instance from so that latency can be kept to a minimum and response is faster. Instances deployed in different regions cannot communicate with each other over a private network. After you buy an instance, you cannot change its region.

    DB Instance Name

    User-defined

    The instance name:

    • Can be the same as an existing instance name.
    • Contains 4 to 64 characters and must start with a letter. It is case-sensitive and allows only letters, digits, hyphens (-), and underscores (_). If the name contains Chinese characters, the length cannot exceed 64 bytes.

    Compatible API

    Cassandra

    -

    DB Instance Type

    Cluster

    -

    DB Engine Version

    3.11

    3.11

    AZ

    AZ 1, AZ 2, and AZ 3

    Availability zone where the instance is created. An AZ is a part of a region with its own independent power supplies and networks. AZs are physically isolated but can communicate through an internal network.

    An instance can be deployed in one or three AZs.

    • If you want to deploy an instance in a single AZ, select one AZ.
    • If you want to deploy an instance across AZs for disaster recovery, select three AZs. Nodes of the instance are evenly distributed across the three AZs.
    Figure 2 Specifications and storage

    Parameter

    Example Value

    Description

    Instance Specifications

    2U8GB

    Select appropriate specifications based on the CPU-memory ratio.

    After an instance is created, you can change its specifications. For details, see Changing vCPUs and Memory of an Instance.

    Nodes

    3

    Number of nodes that the instance is deployed on.

    After an instance is created, you can add nodes. For details, see Adding Nodes.

    Storage Space

    500GB

    Instance storage space. The range depends on the instance specifications. For details, see Instance Specifications.

    After an instance is created, you can scale up its storage if necessary. For details, see Scaling Storage Space.

    Autoscaling

    Toggled off

    Autoscaling is toggled off by default.

    You can toggle it on after an instance is created. For details, see Configuring Auto Scale.

    Disk Encryption

    Disable

    Disable is selected by default.

    If you select Enable, your data will be encrypted on disks and stored in ciphertext after you create an instance. When you download encrypted objects, the ciphertext will be decrypted into plain text and then sent to you. Disk encryption can improve data security and may have slight impacts on database writes and reads.

    Figure 3 Network configuration
    Figure 4 Database configuration

    Parameter

    Example Value

    Description

    VPC

    default_vpc

    Virtual private network where your DB instances are located. A VPC isolates networks for different services. You can select an existing VPC or create a VPC.

    NOTE:
    • After a GeminiDB Cassandra instance is created, its VPC cannot be changed.
    • If you want to connect to an instance using an ECS over a private network, ensure that the GeminiDB Cassandra instance and the ECS are in the same VPC. If they are not, create a VPC peering connection between them.

    Subnet

    default_subnet

    A subnet provides dedicated network resources that are logically isolated from other networks for security purposes.

    Security Group

    default

    A security group controls access between your instance and other services. Ensure that the security group you selected allows your client to access the instance.

    Administrator Password

    Configured based on the password policy

    Password of the administrator account. The password:

    • Can include 8 to 32 characters.
    • Can include uppercase letters, lowercase letters, digits, and any of the following special characters: ~!@#%^*-_=+?
    • For security reasons, set a strong password. The system will verify the password strength.

    Keep your password secure. The system cannot retrieve it if it is lost.

    Parameter Template

    Default-Cassandra-3.11

    A template of parameters for creating an instance. The template contains API configuration values that are applied to one or more instances.

    After an instance is created, you can modify its parameters for optimal performance. For details, see Modifying Parameters of GeminiDB Cassandra Instances.

    Enterprise Project

    default

    This parameter is provided for enterprise users.

    An enterprise project groups cloud resources, so you can manage resources and members by project. The default project is default.

    Select an enterprise project from the drop-down list. For more information about enterprise projects, see Enterprise Management User Guide.

    Retain the default values for other parameters.

  5. On the displayed page, confirm instance details. To modify the configurations, click Previous.
  6. If no modification is required, read and agree to the service agreement and click Submit.
  7. Click Back to Instance Management to go to the instance list.
  8. On the Instances page, view and manage the created instance.
    • It takes about 5 to 9 minutes to create an instance. During the process, the instance status is Creating.
    • After the creation is complete, the status changes to Available.
    Figure 5 Successful purchase

Step 2: Connecting to an Instance Through DAS

DAS enables you to manage DB instances from a web-based console, simplifying database management and improving efficiency. You can connect and manage instances through DAS. By default, you have permission of remote login. DAS is secure and convenient for connecting to DB instances.

Procedure

  1. Log in to the GeminiDB console.
  2. In the service list, choose Databases > GeminiDB Cassandra API.
  3. On the Instance Management page, locate the target DB instance and click Log In in the Operation column.

    Figure 6 Logging in to the database

    Alternatively, click the target instance on the Instance Management page. On the displayed Basic Information page, click Log In in the upper right corner of the page.

    Figure 7 Logging in to the database

  4. On the displayed login page, enter the administrator username and password and click Log In.

    For details about how to manage databases through DAS, see GeminiDB Cassandra Data Management.