Can Nodes Be Added to DDS Instances?

You can add nodes to cluster and replica set instances. Single-node instances do not support adding nodes.

• Cluster instance

  A cluster instance consists of a config node, and multiple dds mongos and shard nodes. Additional shard and dds mongos nodes can be added, but the number of config nodes is fixed.

  For details, see Adding Cluster Instance Nodes.

• Replica set instance

  A replica set consists of the primary node, secondary node, and hidden node. By default, the system provides a three-node replica set. You can add nodes to a five-node or seven-node replica set as required. The newly added nodes are all secondary nodes.

  For details, see Adding Replica Set Instance Nodes.