Key Concepts
The MySQL service consists of the following key concepts:
| Key Concept | Description |
|---|---|
| Instance Group | An object that manages the lifecycle of instances and backups. |
| Instance | A VM managed by the instance group. Its role is determined based on availability—either Primary or Standby. |
| Instance Type | A virtualized hardware resource that includes virtual CPUs (vCPUs) and system memory. - Multiple types are supported to allow optimal MySQL instance selection based on workload. |
| Instance Group/Instance Lifecycle | Allows users to check and manage the operational and task status of instance groups/instances according to their lifecycle stages. |
| Backup | Performed online without database downtime; includes managing creation and deletion of backups. |
| Volume | Provides the database using block storage volumes for MySQL service. - Users do not need to manually create or configure block storage. |
| Network & Security | Provides VPC-based network and security features, allowing you to build logically separated environments depending on network requirements. - All MySQL instances are provided in a VPC environment. |
| IAM & Security | Assigns appropriate access permissions based on user roles via IAM, enabling secure management of MySQL resources. |
| Parameter Group | Manages MySQL configuration parameters by version and group. |
Instance Group
An instance group manages the lifecycle of instances and backups.
MySQL instance groups have various states, including operational and termination statuses. Users can use these to monitor and manage their groups.
Instance group lifecycle and statuses
When you create a MySQL instance group, it starts in the Pending state and transitions through Provisioning and Primary Available before reaching the Available state. In this state, users can access the MySQL instance group through the selected network’s endpoint and port. The default ports are 3306 for Primary and 3307 for Standby, but users can choose any port between 1024 and 65535 during creation.
Lifecycle of MySQL instance group
MySQL Instance Group Lifecycle
| State | Description |
|---|---|
| Pending | Preparing to configure the MySQL instance group. - When you create a new instance group, it begins in the Pending state. |
| Provisioning | Creating instances within the MySQL instance group. |
| Primary Available | Standby instance resources are being allocated and configured. The group is usable. * Availability status of Standby instances is also shown. * HA is maintained and the Primary instance remains available. |
| Switching | A failover (manual or automatic) is currently in progress. |
| Available | All instances in the group are in Running state and ready for use. - Users can access the instance group through its endpoint and selected port. - Default ports: 3306 (Primary), 3307 (Standby). Custom ports allowed: 1024–65535. |
| Scaling-Out | Adding Standby instances to the instance group. |
| Scaling-In | Removing Standby instances from the instance group. |
| Maintenance | Maintenance operations in progress. - Examples: engine version upgrade, OS kernel or version upgrade, restart operations (shelve/unshelve, reboot, apply IOPS). |
| Rebooting | Instance group is currently rebooting. |
| Modifying | Instance group is being updated (e.g., changing security group). |
| Error | One or more instances in the group have encountered errors and are temporarily unavailable. |
| Terminating | All instances are being terminated, and all backups in the instance group are being deleted. |
| Terminated | All instances and backups have been deleted, and the instance group is no longer available. |
Availability status of instance group
When an instance group is in the Primary Available state (Standby resources are being allocated and configured), its operational state (availability) and the availability status of Standby instances are shown together.
| Instance Group State | Availability Status | Description |
|---|---|---|
PRIMARY-AVAILABLE | READY | All Standby HA components are ready. |
PARTIAL-READY | HA configuration is in progress; at least one Standby is ready. | |
PARTIAL-UNAVAILABLE | At least one Standby is ready, and at least one is unavailable. | |
Configured | All Standby configurations are completed. | |
STANDALONE | No Standby is ready, and at least one is unavailable. | |
UNAVAILABLE | All Standby instances are unavailable. | |
AVAILABLE | READY | All Standby instances are ready. |
| - | No Standby instance exists. |
Instance
An instance is a virtual machine (VM) managed by an instance group.
A MySQL instance is a virtualized database including CPU and memory resources, and is a component of a MySQL instance group. Each instance has a state, and its role is determined based on availability: either Primary or Standby.
Instance Roles
| Role | Description |
|---|---|
| Primary | The main instance used for both read and write operations. - Users can access the MySQL instance via DNS. |
| Standby | A high-availability (HA) instance prepared for failover in case the Primary fails. - Created when the instance availability is set to High Availability, or added manually from the instance list. - Also acts as a read-only replica (Read Replica). |
Instance types
MySQL service supports optimized instance types based on the intended use and expected workload.
Each MySQL instance type defines the hardware specifications and configurations for a managed database. When creating a MySQL instance group, you can select the desired instance type, and billing is based on usage. High-performance compute and memory-optimized instance types will be added in the future.
| MySQL Instance Type | vCPU | Memory (GiB) |
|---|---|---|
| m2a.large | 2 | 8 |
| m2a.xlarge | 4 | 16 |
| m2a.2xlarge | 8 | 32 |
| m2a.4xlarge | 16 | 64 |
| m2a.8xlarge | 32 | 128 |
| m2a.12xlarge | 48 | 192 |
| m2a.16xlarge | 64 | 256 |
| m2a.24xlarge | 96 | 384 |
| r2a.large | 2 | 16 |
| r2a.xlarge | 4 | 32 |
| r2a.2xlarge | 8 | 64 |
| r2a.4xlarge | 16 | 128 |
| r2a.8xlarge | 32 | 256 |
| r2a.12xlarge | 48 | 384 |
| r2a.16xlarge | 64 | 512 |
| r2a.24xlarge | 96 | 768 |
Instance lifecycle and status
An instance starts in the Pending state, transitions through Provisioning and Starting, and finally reaches the Running state.
MySQL Instance Lifecycle
| Status | Description |
|---|---|
Pending | Preparing the instance configuration. |
Starting | Setting up and initializing the MySQL database. |
Restarting | Restarting the MySQL process. |
Running | The instance is running and available for use. |
Volume-Extending | The instance volume is currently being extended. |
Engine-Upgrade | The MySQL engine is being upgraded. |
Kernel-Upgrade | The OS kernel is being upgraded. |
OS-Upgrade | The operating system is being upgraded. |
Reboot | The instance is being rebooted. |
Error | An error has occurred, making the instance temporarily unavailable. Triggered by database or API request failures. |
Terminating | The instance is being terminated and returned. |
Terminated | The instance is fully terminated and no longer available. |
Instance availability configuration and roles
The number and roles of instances vary depending on the chosen availability configuration.
| Availability Mode | Number of Instances | Description |
|---|---|---|
| Single (Primary only) | 1 | Only one Primary instance is created. |
| High Availability (HA: Primary + Standby) | Up to 6 | One Primary instance and 1–5 Standby instances are created. |
Instance availability states
These states represent the data replication status between MySQL instances. Applicable only to instance groups configured with High Availability.
MySQL Instance Availability States
| Availability State | Description |
|---|---|
CONFIGURED | Data replication between MySQL instances is functioning properly. |
CONFIGURING | Replication setup is in progress. |
DELAYING | Replication delay exceeds 60 seconds. |
WARNING-SYNC | The Standby instance holds more data than the Primary. |
UNAVAILABLE | Data replication has stopped. |
Backup
Backups are managed on a MySQL instance group basis.
Backup lifecycle and statuse
Backups begin in the Pending state, transition through Processing, and are considered complete when they reach the Succeeded state.
Backups created before and after March 19, 2024, follow different lifecycles for operations like restore and delete.
Backup Status (Created before March 19, 2024)
MySQL Backup Lifecycle (Before March 19, 2024)
| Status | Description |
|---|---|
Pending | Initial state of the backup. |
Processing | Backup is in progress. |
In-Use-Checking | Verifying whether the backup is currently used for restoration before deletion. |
Deletion-Pending | Backup is queued for deletion but currently used for restoration (deletes after restore finishes). |
Deleted | Backup has been completely removed. |
Succeeded | Backup completed successfully. |
Deleting | Backup is in the process of being deleted. |
Fatal | Internal logic failure occurred. |
Error | Abnormal termination of backup process. – Triggered by DB or external API failures during backend logic. |
Backup Status (Created after March 19, 2024)
MySQL Backup Lifecycle (After March 19, 2024)
| Status | Description |
|---|---|
Pending | Initial state of the backup. |
Processing | Backup is in progress. – Even if deletion is requested, it will only occur after the backup succeeds or fails. |
Restoring | Currently used for restoration and cannot be deleted. |
Deleted | Backup has been completely removed. |
Succeeded | Backup completed successfully. |
Deleting | Deletion in progress. – If the backup is used for restore, the state transitions to Restoring. |
Error | Backup failed. – Cannot be restored but can be deleted. |
Failover
MySQL supports High Availability (HA). When selecting HA for an instance group, multiple Standby instances can be created, and Failover ensures service continuity in case of failure.
Both automatic failover and manual failover are supported.
Service interruption may occur during failover.
Failover lifecycle
Instance Group States During Failover
| Status | Description |
|---|---|
SWITCHING | Failover is in progress. MySQL service is unavailable. |
PRIMARY-AVAILABLE | Standby instance setup is in progress. |
Volume
MySQL uses block storage devices to provide database storage.
Users are not required to manually create or configure block storage.
Network and security
All MySQL instances operate within a VPC environment.
VPC offers networking and security capabilities, enabling logically isolated environments based on specific network requirements.
See the VPC documentation for more details.
Parameter group
MySQL configuration parameters can be grouped and managed together.
Parameter synchronization status
Parameter Group Sync Status
| Status | Description |
|---|---|
Pending | Waiting to apply parameter changes. |
Applying | Applying parameters to the instance group. |
In-Sync | Parameters have been successfully applied to all instances in the group. |
Partial-Sync | Parameters were only partially applied due to instances not being in a state (e.g., Failover, Provisioning) that allows syncing. – Once successful, the status changes to In-Sync, otherwise it becomes Error-Sync. |
Error-Sync | Parameter sync failed. You can retry the sync, which changes the state to Applying. |
Suspended | Sync is paused because a previous instance group failed to apply parameters. – Retry is possible and will change the state to Applying. |