MySQL Constraints

Table 1 shows the constraints designed to ensure the stability and security of RDS for MySQL.

**Table 1** Function constraints
Function Item	Constraints
Database access	If public accessibility is not enabled for the RDS DB instance, the RDS DB instance must be in the same VPC as the ECS. RDS read replicas must be created in the same subnet as the primary DB instance. The security group must allow access from an ECS. By default, RDS cannot be accessed through an ECS in a different security group. You need to add an inbound rule to the RDS security group. The default RDS port is 3306. You can change it if you want to access RDS through another port.
Deployment	ECSs in which DB instances are deployed are not visible to users. You can access the DB instances only through an IP address and a port number.
Database root permissions	Only the root user permissions are provided on the instance creation page.
Database parameter modification	Most parameters can be modified on the RDS console.
Data import	Through the command-line interface (CLI) or graphical user interface (GUI) Through MySQL CLI tools For details, see Migrating Data to RDS for MySQL Using mysqldump.
MySQL storage engine	For details, see What Storage Engines Does the RDS for MySQL Support?
Database replication setup	RDS for MySQL provides a dual-node cluster with the primary/standby replication architecture. You do not need to set up replication. The standby DB instance is not visible to users and therefore you cannot access it directly.
DB instance reboot	RDS DB instances cannot be rebooted through commands. They must be rebooted on the RDS console.
RDS backup files	RDS backup files are stored in OBS buckets and are not visible to users.