You can easily migrate self-built MongoDB databases to ApsaraDB for MongoDB instances. However, ApsaraDB for MongoDB has some constraints to be aware of.
| Operation | Constraint |
|---|---|
| Database root permission | Root permissions are unavailable to users. |
| Modify database parameters | Currently, parameter modification functions are not supported. |
| Create database copy | The system automatically creates a three-node ReplicaSet. Of the three nodes, the primary and secondary nodes are provided to the users. The standby node is invisible to the users. Currently, users cannot manually create a secondary node. |
| Restart database | The instance must be restarted on the console. |
| Data migration | The command line or graphical interface can be used to perform logical import. Currently, no official data import tool is provided. |
| Storage engine | MongoDB 3.2 is currently supported. Only the WiredTiger storage engine is supported and the storage engine cannot be modified. |
| Build a cluster | You can create a cluster version instance on the sales page. Select the configuration and quantity of Mongos and shard nodes (each node contains the three-node ReplicaSet), and specify a ConfigServer. Clusters are maintained by Alibaba Cloud’s MongoDB O&M team. |