Overview

Managing data nodes is managing RDS for MySQL instances that are associated with your DDM instance. You can view the RDS instance status, storage, node class, and read weight, configure read weights, synchronize data node information, and enable read/write splitting.

**Table 1** Functions
Function	Description
Synchronizing data node information	This function is used to synchronize data node changes to your DDM instance after you make changes such as adding or deleting a read replica, changing the connection address, port number, or specifications, or deleting a data node.
Enabling or disabling read/write splitting	This function is used for DDM kernel version 3.1.0 or later. If the DDM kernel version is 3.1.0 or later, you need to manually enable read/write splitting and then adjust read/write weights of your primary instance and read replicas. You can also manually disable read/write splitting as needed. If the DDM kernel version is earlier than 3.1.0, read/write splitting is enabled by default and cannot be disabled. You just need to adjust read/write weights of your primary instance and read replicas.
Configuring read weights	This function is used when you need to adjust read/write weights of your primary instance and read replicas to split read and write requests. You can configure read/write weights of multiple instances in batches. If a data node (associated DB instance) has no read replicas, you cannot configure a read/write weight for it.