Buying a Replica Set Instance

Prerequisites

• You have registered a Huawei Cloud account.

Procedure

1. Log in to the management console.
2. In the service list, choose Databases > GeminiDB Mongo API.
3. On the Instances page, click Buy DB Instance.
4. On the displayed page, select a billing mode, specify instance specifications and click Next.
   Figure 1 Billing mode and basic information
   

   Table 1 Billing mode

   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 to optimize costs. 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 DB Instance. Pay-per-use If you select this billing mode, you are billed based on how much time the instance is in use. If you expect to use an instance for a long period of time, change its billing mode to yearly/monthly to optimize costs. For details, see Changing the Billing Mode from Pay-per-Use to Yearly/Monthly.

   Table 2 Basic information

   Parameter	Description
   Region	The region where the instance is deployed. NOTICE: Select the region nearest where you will be accessing the DB from so latency can be kept to a minimum and response time will be faster. Instances deployed in different regions cannot communicate with each other through 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 Modifying the Name of an Instance.
   Compatible API	MongoDB
   DB Instance Type	Replica set
   DB Engine Version	4.0
   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. In this deployment mode, the nodes are evenly distributed across the three AZs.

   Figure 2 Specifications and storage
   

   Table 3 Specifications and storage

   Parameter	Description
   Instance Specifications	The CPU and memory of a DB instance. Different performance specifications support different numbers of connections and maximum IOPSs. Select CPU and memory specifications based on your service requirements.
   Storage Space	Storage space depends on the instance specifications. The minimum storage space is 100 GB, and the storage space you set must be an integer.

   Figure 3 Network and database configuration
   

   Table 4 Network

   Parameter	Description
   VPC	The virtual network where your DB instances are located. A VPC isolates networks for different services. You can select an existing VPC or create a VPC. For details about how to create a VPC, see section "Creating a VPC" in the Virtual Private Cloud User Guide. With VPC sharing, you can also use a VPC and subnet shared by another account. VPC owners can share the subnets in a VPC with one or multiple accounts through Resource Access Manager (RAM). This allows for more efficient use of network resources and reduces O&M costs. For more information about VPC subnet sharing, see VPC Sharing in the Virtual Private Cloud User Guide. If there are no VPCs available, the system allocates resources to you by default. NOTE: After the GeminiDB Mongo instance is created, the VPC where the instance resides cannot be changed. If you want to connect to a GeminiDB Mongo instance through an ECS over an internal network, the instance and the ECS must be in the same VPC. If they are not in the same VPC, you can create a VPC peering connection to enable access.
   Subnet	A subnet provides dedicated network resources that are logically isolated from other networks, improving network security. NOTE: IPv6 subnets are not supported. You are advised to create and select IPv4 subnets.
   Security Group	A security group controls access between GeminiDB Mongo instances and other services. When you select a security group, you must ensure that it allows the client to access DB instances. If there are no security groups available, the system allocates resources to you by default.
   SSL	Secure Sockets Layer (SSL) encrypts 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, you can connect to it using SSL. NOTE: This function is in the open beta test (OBT) phase. To use this function, contact customer service. If SSL is not enabled when you create an instance, you can enable it after the instance is created. For details, see Configuring an SSL Connection.
   Access Across CIDR Blocks	Access across CIDR blocks is required only when the CIDR blocks of the client and the replica set instance are different. For example, if the client CIDR block is 192.168.0.0/16 and the replica set instance's CIDR block is 172.16.0.0/24, add the CIDR block 192.168.0.0/16 so that the client can access the replica set instance. You can configure cross-CIDR block access when creating a DB instance or after the instance is created. Configure When creating a DB instance, add the CIDR block of the source client (for example, the client that accesses the replica set instance). After the DB instance is created, you can connect to the DB instance from the source client. If there are multiple CIDR blocks, click to add them in sequence. Up to 9 CIDR blocks can be configured, but they cannot overlap. NOTE: To ensure the ECS and the DB instance can communicate with each other, configure the connection by referring to VPC Peering Connection Overview. Skip Configure the CIDR block of the client later. After a DB instance is created, you can configure access across CIDR blocks by referring to Configuring Access Across CIDR Blocks.

   Table 5 Database configuration

   Parameter	Description
   Administrator	The default administrator account is rwuser.
   Administrator Password	Set a password for the administrator. The password: Must be 8 to 32 characters long. Must contain uppercase letters, lowercase letters, digits, and any of the following special characters: ~!@#%^*-_=+? For security reasons, you must select a strong password. The system will verify the password strength. Keep this password secure. If you lose it, the system cannot retrieve it.
   Confirm Password	Enter the administrator password again.
   Parameter Template	A parameter template contains API configuration values that can be applied to one or more instances. After an instance is created, you can modify its parameters to better meet your service requirements. For details, see Modifying Parameters of GeminiDB Mongo Instances. NOTICE: When an instance is created, the system uses default values for specification parameters in your customer 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.

   Table 6 Tags

   Parameter

   Description

   Tags

   This setting is optional. Adding tags helps you better identify and manage your instances. By default, each instance supports up to 10 tags. 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. If your organization has configured tag policies for GeminiDB Mongo, you need to add tags to instances based on the tag policies. If a tag does not comply with the policies, DB instance creation may fail. Contact your organization administrator to learn more about tag policies. Tag key: Mandatory if the instance is going to be tagged. Each tag key must be unique for each instance. The key 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 a DB instance is created, you can view its tag details on the Tags tab. In addition, you can add, modify, and delete tags for existing DB instances. For details, see Managing Tags.

   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	By default, this option is not selected. If you select this option, the renew cycle is the same as the selected duration.

   Table 8 Quantity

   Parameter	Description
   Quantity	GeminiDB Mongo instances can be created in batches. Up to 50 DB instances can be created at a time.

5. On the displayed page, confirm the instance details.
   • For yearly/monthly instances
     • If you need to modify the settings, click Previous.
     • If you do not need to modify the settings, read and agree to the service agreement and click Pay Now to go to the payment page and complete the payment.
   • For pay-per-use instances
     • If you need to modify the settings, click Previous.
     • If no modification is required, read and agree to the service agreement and click Submit.

6. On the Instances page, view and manage your instances.
   • Creating a DB instance takes about 5 to 9 minutes. During the process, the instance status displayed in the DB instance list is Creating.
   • After the creation is complete, the status changes to Available.

     You can click in the upper right corner of the page to refresh the DB instance statuses.

   • During creation, an automated backup policy is enabled by default. A full backup is automatically triggered after a DB instance is created.