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What Is DDS?

Document Database Service (DDS) is compatible with MongoDB and is secure, highly available, reliable, scalable, and easy to use. It provides DB instance creation, scaling, redundancy, backup, restoration, monitoring, and alarm reporting functions with just a few clicks on the DDS console.

Why DDS?

  • Automatically sets up three-node replica set architecture. DDS supports fast deployment, high availability (HA) data storage, data redundancy, and failover support.
  • Provides sharded cluster instances consisting of shard, mongos, and config, enabling you to easily enhance read and write performance and build a distributed DDS database system.
  • Provides database backup and restoration functions in one-click mode. Allows you to back up and restore the database on the console.
  • Provides performance metrics and sets alarms on any of the metrics to send you notification. You can quickly monitor instance status and identify issues at a glance.

For more details, see Comparison Between DDS and On-Premises Database and Typical Application Scenarios.

How to Access DDS?

HUAWEI CLOUD provides a web-based service management platform. You can access DDS through HTTPS-based application programming interfaces (APIs) or the management console. These two access modes differ as follows:

  • Accessing DDS through the management console

    If you have registered an account, click Document Database Service under Database on the console homepage to access DDS.

    If you have not registered with HUAWEI CLOUD, follow the instructions provided in Common Operations to register an account at HUAWEI CLOUD official website.

  • Accessing DDS through APIs

    You can code an API call to access DDS. For details, see the Document Database Service API Reference.

Compatible DB Engines and Versions

For details about the compatible DB engines and versions, see Database Engine and Version.

Product Architecture

DDS supports multiple deployment modes to meet different service scenarios.

Table 1 Architecture description

Instance Architecture



The DDS cluster consists of three types of nodes: mongos, shard, and config. The architecture of these nodes varies. You can configure the number of mongos and shard nodes as required. mongos uses a single-node architecture, and shard and config use a three-node replica set architecture. For details, see Cluster Architecture (Community Edition).

Replica set

In the replica set instance, there are three types of nodes: primary, secondary, and hidden. You can operate the primary and secondary nodes directly. A replica set instance supports DR switchover and high availability. It is transparent to your applications. For details, see Replica Set Architecture.

Single node

Single-node instance is designed for development, testing, and storing non-core data of enterprises. It brings you visualized O&M and elastic scaling at a lower price. For details, see Single Node Architecture.

Product Pricing

For details, see Product Pricing Details.

Deployment Suggestions

It is recommended that you deploy DDS by considering the following factors:

  • Region and Availability Zone (AZ) describe the location of DDS DB instances. Once the DB instance is successfully created, the region cannot be changed. You can select regions and AZs based on the geographical locations of users, product prices, DR capabilities, and network latency. For more information, see Region and AZ.
  • Network planning: When creating a DDS DB instance, you are advised to use the VPC and subnet where the ECS is deployed.
  • Data security: DDS provides comprehensive security assurance for the data security that you may concern. You can deploy DB instances in multiple AZs and use audit logs, isolated networks, security groups, and data encryption to ensure data security.
    • Elastic Cloud Server (ECS)
    • Virtual Private Cloud (VPC)