Baidu AI Cloud database DocDB for MongoDB provides two architectures, replica set and cluster shard for business scenarios with different data sizes.

Replica set architecture instances are suitable for small - and medium-sized business scenarios. After the data is written to the instance, it is asynchronously copied into three parts and stored in the Primary node, Secondary node and Hidden node. When single node failure occurs, the reliability of data will be guaranteed. You can directly operate Primary node or a Secondary node.

Architecture Diagram of Three Node Replica Set

Instances of a cluster shard architecture are suitable for applications with larger data volumes, higher IOPS, and linking numbers. The shard cluster architecture instance provides Mongos (service proxy), Shard (shard server) and ConfigServer. You can choose the number and configuration of “Mongos” and “Shard” nodes based on performance and storage capacity requirements.

Architecture Diagram of Cluster shard Set