Updated on 2023-11-21 GMT+08:00

Buying an Instance

This section describes how to buy a GeminiDB Cassandra instance that is compatible with Cassandra APIs.

Each tenant can have up to 50 GeminiDB Cassandra instances by default. To request a higher quota, contact customer service.

Prerequisites

  • You have registered a Huawei Cloud account.

Procedure

  1. Log in to the management 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, specify a billing mode and instance specifications and click Next.

    Figure 1 Billing mode and basic information
    Table 1 Billing parameters

    Parameter

    Description

    Billing Mode

    Method that the instance is billed in. The value can be Yearly/Monthly or Pay-per-use.

    • Yearly/Monthly
      • In this mode, specify Required Duration at the bottom of the page. The system deducts the fees incurred from your account based on the service price.
      • If you do not need such an instance any longer after it expires, change the billing mode to pay-per-use. For details, see Changing the Billing Mode from Yearly/Monthly to Pay-per-Use.
        NOTE:

        Yearly/Monthly instances cannot be deleted directly. If such an instance is no longer required, unsubscribe from it. For details, see Unsubscribing from a Yearly/Monthly Instance.

    • Pay-per-use
    Table 2 Basic information

    Parameter

    Description

    Region

    The region where the instance is deployed.

    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

    The instance name:

    • Can be the same as an existing instance name.
    • Can include 4 to 64 bytes and must start with a letter. It is case-sensitive and allows only letters, digits, hyphens (-), and underscores (_).

    After an instance is created, you can change its name. For details, see Changing an Instance Name.

    Compatible API

    Cassandra

    DB Instance Type

    Cluster

    DB Engine Version

    3.11

    AZ

    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
    Table 3 Specifications and storage

    Parameter

    Description

    Instance Specifications

    Decoupled storage and compute and software-hardware synergy deliver twice or more the performance of an on-premises database with the same specifications. When you create an instance, select higher specification and specify as few nodes as possible. For example, if you need 8 vCPUs, 32 GB, and 6 nodes for an on-premises deployment, then for a GeminiDB Cassandra instance with 8 vCPUs and 32 GB of memory, you only need 3 nodes.

    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

    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

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

    Select at least 1 GB each time you scale up the storage, and ensure that the increment is an integer.

    Enable autoscaling to ensure that the instance has sufficient storage and keeps available. To enable this function, just switch on button Configure Autoscaling and set the following parameters:

    • If available storage drops to or below: The storage threshold for triggering autoscaling. When the percentage of available storage drops to or below the threshold you set or 10 GB, the system automatically scales up your instance storage.
    • Increase by: The percentage that your instance storage will be scaled up at. If the increased storage is not a multiple of 10 GB, the system will round it up to the nearest multiple of 10 GB. At least 100 GB is added each time.
    • Autoscaling Limit: Maximum amount that the system can automatically scale up an instance's storage space to. The value must be no less than the total storage of the instance and cannot exceed its maximum storage.

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

    NOTE:
    • Once autoscaling is enabled, an agency will be created and fees will be automatically deducted from your account.
    • Autoscaling is available only when you have the required permission. To enable this function, contact customer service.
    • You can enable autoscaling after an instance is created. For details, see Configuring Autoscaling.

    Disk Encryption

    You can select to enable disk encryption based on service requirements.

    • Disabled: Data storage is not encrypted.
    • Enabled: Data store is encrypted. If you select this option, your data will be encrypted on disks and stored in ciphertext after you create a DB 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.

      Key Name: Select an existing key or create one.

      NOTE:
      • This function is in the open beta test (OBT) phase. To use it, contact customer service.
      • An agency will be created after disk encryption is enabled.
      • After an instance is created, the disk encryption status and the key cannot be changed.
      • The key cannot be disabled, deleted, or frozen when being used. Otherwise, the database becomes unavailable.
      • For details about how to create a key, see "Creating a CMK" in Data Encryption Workshop User Guide.
    Figure 3 Network configuration
    Table 4 Network configuration

    Parameter

    Description

    VPC

    The virtual network where the instance is created. A VPC isolates networks for different services. You can select an existing VPC or create one.

    If there are no VPCs available, the system automatically allocates a VPC to you.

    For details, see "Creating a VPC" in the Virtual Private Cloud User Guide.

    NOTE:
    • After a GeminiDB Cassandra instance is created, its VPC cannot be changed.
    • If you want to connect to a GeminiDB Cassandra instance from 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 for access.

    Subnet

    A subnet where your instance is created. The subnet provides dedicated and isolated networks, improving network security.

    NOTE:

    Create an IPv4 subnet or select an existing one. IPv6 subnets are not supported.

    Security Group

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

    If there are no security groups available, the system allocates one to you by default.

    SSL

    A security protocol. Secure Sockets Layer (SSL) certificates set up encrypted connections between clients and servers, preventing data from being tampered with or stolen during transmission.

    You can enable SSL to improve data security. After an instance is created, connect to the instance through SSL. For details, see SSL.

    NOTE:

    After SSL is enabled, it cannot be disabled.

    Figure 4 Database configuration
    Table 5 Database configuration

    Parameter

    Description

    Administrator

    Username of the administrator account. The default value is rwuser.

    Administrator Password

    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.

    Confirm Password

    This password must be consistent with administrator password.

    Parameter Template

    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 a Parameter Template.

    Enterprise Project

    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.

    Figure 5 Tag configuration
    Table 6 Tags

    Parameter

    Description

    Tags

    This setting is optional. Adding tags helps you better identify and manage your GeminiDB Cassandra instances.

    Each instance supports up to 10 tags by default. To use more tags, contact customer service to apply for a quota of 20 tags.

    A tag consists of a tag key and a tag value.

    • Tag key: Mandatory if the instance is going to be tagged

      Each tag key is unique for each instance. It can include up to 36 characters, including digits, letters, underscores (_), and hyphens (-).

    • Tag value: Optional if the instance is going to be tagged

      The value can contain up to 43 characters, including digits, letters, underscores (_), periods (.), and hyphens (-).

    After an instance is created, you can view its tags on the Tags page and can also add tags to, modify, and delete tags of your instance. For details, see Managing Tags.

    Figure 6 Required duration configuration
    Table 7 Required duration

    Parameter

    Description

    Required Duration

    The length of your subscription if you select Yearly/Monthly billing. Subscription lengths range from one month to three years.

    Auto-renew

    • This option is not selected by default.
    • If you select this option, the auto-renew cycle is determined by the selected required duration.

  5. On the displayed page, confirm the instance details.

    • For yearly/monthly instances
      • If you need to modify the settings, click Previous to modify parameters.
      • If no modification is required, read and agree to the service agreement and click Pay Now.
    • For pay-per-use instances
      • If you need to modify the settings, click Previous to modify parameters.
      • If no modification is required, read and agree to the service agreement and click Submit.

  6. To view and manage your instance, go to the Instances page.

    • 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.

      You can click in the upper right corner to refresh the instance status.

    • Automated backup is enabled by default during instance creation. After the instance is created, a full backup is created.