PolarDB:Purchase a pay-as-you-go cluster

Prerequisites

You have an Alibaba Cloud account. For instructions, see Sign up for and log in to an Alibaba Cloud account.

Procedure

1. Go to the PolarDB cluster purchase page.

2. Configure the basic settings for your cluster. The following table describes the parameters.

   Parameter	Description
   Billing Method	Subscription: You select fixed-specification resources and pay upfront. Longer periods offer larger discounts. Best for stable, long-term workloads. Pay-as-you-go: You select fixed-specification resources and pay only for actual usage, with no upfront cost. Best for flexible workloads. Serverless: A pay-as-you-go model. PolarDB automatically scales resources based on workload, with no upfront cost or specification selection. Best for fluctuating, uncertain, or unpredictable workloads. Note For a detailed comparison of billing methods, see Billing methods. Change billing method rules: subscription and pay-as-you-go can be converted to each other, but the billing method for Serverless cannot be changed.
   Region	A region is the geographical area of a data center. Regions are typically named after the city where the data center resides. Note To reduce network latency, choose a region close to your users. The region cannot be changed after the cluster is created. For optimal performance, create your PolarDB cluster in the same region as the connecting ECS instances. Otherwise, they cannot communicate over the internal network and must use the public network, which degrades performance.
   Creation Method	PolarDB supports multiple creation methods. The default option is Create Primary Cluster, which creates a new PolarDB cluster. The other options are described as follows: Create secondary cluster: Creates a secondary cluster for a Global Database Network (GDN). You must create a GDN before you can add a secondary cluster. Upgrade/Migrate from PolarDB: Upgrades the major version between different kernel versions or series. This method first performs a full data copy from the source PolarDB cluster and then maintains incremental data synchronization. For more information, see Major version upgrades. Migrate from RDS: Migrates an RDS instance to a PolarDB cluster. The system automatically synchronizes accounts, databases, the IP whitelist, and necessary parameter configurations from the RDS instance. You can also retain the original database endpoint to simplify migration and ensure a smooth business transition. For more information, see One-click upgrade from an RDS for MySQL instance to a PolarDB for MySQL cluster. Note The list of available RDS instances excludes read-only instances and instances that use non-InnoDB engines. Clone from RDS: You can quickly clone a PolarDB cluster with the exact same data from a selected RDS instance. This creation method does not synchronize incremental data from the RDS instance to the PolarDB cluster. For more information, see One-click clone from RDS for MySQL to PolarDB for MySQL. Note The list of available RDS instances excludes read-only instances and instances that use non-InnoDB engines. Restore From Recycle Bin: Restores a deleted PolarDB cluster from a backup in the cluster recycle bin. Note If the original PolarDB cluster had X-Engine enabled, you must select InnoDB & X-Engine for the Storage engine parameter. Otherwise, the new PolarDB cluster cannot access the data in X-Engine.
   Database Engine	Select a MySQL-compatible version. MySQL 8.0.2: Fully compatible with community MySQL 8.0.18 and earlier versions. MySQL 8.0.1: Fully compatible with community MySQL 8.0.13 and earlier versions. MySQL 5.7: Fully compatible with MySQL 5.7. MySQL 5.6: Fully compatible with MySQL 5.6. Note Features vary by kernel version. For more information, see Feature comparison of versions 5.6, 5.7, and 8.0.
   Database Edition	You can select Enterprise Edition or Standard Edition. Note Features vary by edition. For more information, see Feature comparison between Enterprise Edition and Standard Edition.
   Edition	Enterprise Edition supports two series: Cluster and Multi-master Cluster (Limitless). This option is not available for Standard Edition. Note The two series have different architectures and use cases. For more information, see Enterprise Edition series.
   Specification Edition	You can select a Dedicated or a General-purpose: Dedicated specification: Each cluster has exclusive access to its allocated computing resources, such as CPU, and does not share them with other clusters on the same server. This ensures more stable and reliable performance. General-purpose specification: Different clusters on the same server share and fully utilize each other's idle computing resources, such as CPU. This resource multiplexing provides better cost-effectiveness by taking advantage of economies of scale. For a detailed comparison of the two specification types, see How to choose between general-purpose and dedicated specifications.
   CPU Architecture	You can select X86 or ARM. Note The CPU architecture for Enterprise Edition is fixed to X86.
   Primary Zone	An availability zone is a physical zone within a region that has independent power and networking. There is no substantial difference between different availability zones. You can create your PolarDB cluster and ECS instances in the same or different availability zones.
   Network Type	The value is fixed to VPC. We recommend that you select the same VPC as the ECS instances that need to connect to the cluster. Otherwise, they cannot communicate over the internal network, which prevents the cluster from delivering optimal performance. If you have already created a VPC that meets your network requirements, you can select it directly. For example, if you have an ECS instance in a VPC that meets your requirements, select that VPC. If you do not have a suitable VPC, you can use the default VPC and vSwitch. Note If the default VPC and vSwitch do not meet your requirements, you can create a VPC and a vSwitch.
   Add to whitelist	We recommend that you Enable this option. This adds the CIDR block of your selected VPC to the PolarDB cluster's whitelist, allowing ECS instances in the same VPC to directly access the PolarDB cluster. This eliminates the need to manually configure the whitelist after the cluster is created.
   HA Mode	PolarDB provides multiple high availability modes. After you enable the hot standby storage cluster feature for a PolarDB cluster, a hot standby storage cluster is created in the secondary zone of the region in which the PolarDB cluster resides or in a different data center in the same zone. The hot standby storage cluster has independent storage resources. Whether the hot standby storage cluster has independent compute resources varies based on the high availability mode. When the PolarDB cluster in the primary zone fails, the hot standby storage cluster immediately takes over and handles read and write operations and storage tasks. Note For more information about the hot standby storage cluster and related solutions, see High availability modes (hot standby clusters). Rules for changing high availability modes: You cannot directly change the high availability mode of a cluster from Double Zones (Hot Standby Storage Cluster Enabled) or Double Zones (Hot Standby Storage and Compute Clusters Enabled) to Single Zone (Hot Standby Storage Cluster Disabled). For such change of the high availability mode, we recommend that you purchase a new cluster and select the Single Zone (Hot Standby Storage Cluster Disabled) high availability mode for the cluster. Then, migrate the existing cluster to the new cluster by using Data Transmission Service (DTS). For information about how to migrate an existing cluster to a new cluster, see Migration between PolarDB for MySQL clusters. You can select the Three Zones high availability mode only when you purchase a new cluster. You cannot change the high availability mode of a cluster from Three Zones to other high availability modes and vice versa. You can manually change the high availability mode of a cluster from Single Zone (Hot Standby Storage Cluster Disabled) to a different high availability mode. For more information, see High availability modes (hot standby clusters).
   Configure Serverless cluster resource scaling range	You can set the resource scaling range of a Serverless cluster only when the billing method is Serverless: Minimum Read-only Nodes: The minimum number of read-only nodes. Valid values: 0 to 15. Maximum Read-only Nodes: The maximum number of read-only nodes. Valid values: 0 to 15. Note The number of read-only nodes automatically scales up or down within the specified range based on the workload. For more information about the scaling policy, see Auto scaling. To ensure high availability for your serverless cluster, we recommend setting Minimum Read-only Nodes to 1. Minimum PCUs per Node: The minimum number of PCUs for each node in the cluster. Valid values: 0.25 to 31 PCUs. Maximum PCUs per Node: The maximum number of PCUs for each node in the cluster. Valid values: 1 to 32 PCUs. Note Serverless uses PCUs as the unit for per-second billing and resource scaling. One PCU is equivalent to approximately 1 vCPU core and 2 GB of memory. The PCUs of a node dynamically scale within the specified range, with a minimum scaling step of 0.5 PCU. Example: If you set Minimum PCUs per Node to 2 and Maximum PCUs per Node to 16, the default specification for each node in the serverless cluster is 2 PCUs (about 2 vCPU cores and 4 GB of memory). When the system detects an increase in workload, it automatically scales up the PCUs of the primary node or read-only nodes. However, the number of PCUs cannot exceed 16.
   Current specification	Specifications differ in terms of CPU, memory, maximum storage capacity, and IOPS. Select a specification based on your business requirements. Note The available compute node specifications vary based on the Database Edition. For more information, see Compute node specifications for Enterprise Edition and Compute node specifications for Standard Edition.
   Enable Serverless	You can enable the Serverless feature for a cluster with fixed specifications when you create the PolarDB cluster. When enabled, the cluster can dynamically scale resources beyond the fixed specifications based on workload. However, this incurs corresponding scale-up fees. Note The default Serverless configuration is as follows: a single-node elasticity range of 0 to 8, and a read-only node range of 0 to 1. You can adjust these configuration parameters on the cluster details page at any time after the cluster is created.
   Nodes	The default is two nodes (one primary node and one read-only node). You can configure the number of nodes based on your business requirements. Note Only Enterprise Edition clusters of the Multi-master Cluster (Limitless) Edition series can have multiple primary nodes. Other series support only one primary node. The single-node series is no longer available. However, you can purchase a single-node PolarDB cluster by setting the number of Read-only Node to 0. If you set the number of read-only nodes to 1 or more when you purchase a cluster, you cannot change this number to 0 later. To reduce the number of read-only nodes in an existing cluster to 0, we recommend that you purchase a new cluster and migrate data from the original cluster by using a migration tool such as DTS or the major version upgrade feature. Node types: Primary Node: Handles write and some read operations. It works with read-only nodes in an active-active failover configuration to ensure high availability. Read-only Node: Handles read operations to offload the primary node, providing high availability and scalability. After creating the cluster, you can dynamically adjust the number of read-only nodes based on your business needs. Read-only IMCI Node: A functional node for the In-Memory Columnar Index (IMCI) feature. IMCI uses columnar storage technology to accelerate online analytical processing (OLAP) queries. This allows a PolarDB for MySQL cluster to provide both real-time transaction processing and real-time data analysis. After you add an IMCI read-only node, you must also configure a plan for automatic request distribution between row-based and column-based nodes and add columnar indexes to your business tables. OLAP query requests will then be automatically routed to read-only row-based or column-based nodes instead of the primary node.
   PolarProxy specification	The supported proxy types are Standard Enterprise Edition and Dedicated Enterprise Edition. The proxy type depends on the cluster's specification type. General-purpose specification clusters use Standard Enterprise Edition, while dedicated specification clusters use Dedicated Enterprise Edition. The PolarProxy specification can be configured separately, with options ranging from 4 to 16 vCPUs. We recommend that you select automatic matching. Note This parameter can be configured only for Standard Edition clusters.
   Storage Type	PolarDB supports ESSD, PSL4, and PSL5 storage types. Standard Edition clusters support only ESSD cloud disks. ESSDs are ultra-high-performance disks built on a distributed block storage architecture with 25 Gigabit Ethernet and Remote Direct Memory Access (RDMA) support, delivering up to 1 million random read/write IOPS at low one-way latency. PL0 ESSD: A performance level (PL) 0 ESSD. PL1 ESSD: A PL1 ESSD delivers five times the IOPS and approximately twice the throughput of a PL0 ESSD. PL2 ESSD: A PL2 ESSD delivers approximately twice the IOPS and throughput of a PL1 ESSD. PL3 ESSD: A PL3 ESSD delivers up to 10 times the IOPS and 5 times the throughput of a PL2 ESSD. It is suitable for business scenarios that require extremely high concurrent I/O performance and stable, low read/write latency. AutoPL ESSD: Compared to PL0, PL1, PL2, and PL3 ESSDs, AutoPL ESSDs decouple IOPS from capacity, allowing for flexible configuration and on-demand adjustments. This reduces the overall Total Cost of Ownership (TCO). Important For more information about the performance of ESSD cloud disks, see ESSD cloud disks. When an ESSD cloud disk's storage space is full, it becomes read-only. To avoid business disruptions, you can enable automatic storage scaling for ESSD cloud disks. PSL4 and PSL5 are storage types that PolarDB provides for different business scenarios. The differences are as follows: Storage type Features Use cases PSL5 (PolarStore Level 5) This storage class was used in earlier versions of PolarDB and is the default for clusters purchased before June 7, 2022. It offers higher performance, reliability, and availability. Business-critical workloads that require high performance and reliability, such as finance, e-commerce, government services, and medium-to-large internet businesses. PSL4 (PolarStore Level 4) A new PolarDB storage class that uses Alibaba's proprietary smart-SSD technology. This technology compresses and decompresses data at the physical SSD layer, which reduces storage costs with a manageable performance impact. Cost-sensitive applications that prioritize high cost-effectiveness. Note Storage class conversion rules: Some product series support upgrading the storage class from PSL4 to PSL5. Downgrading the storage class is not supported. You cannot downgrade PSL5 storage to PSL4 storage. To switch from PSL5 storage to PSL4 storage, purchase a new cluster and migrate the data using either a migration tool like Data Transmission Service (DTS) or a major version upgrade.
   Storage engine	You can select InnoDB or InnoDB & X-Engine. Note InnoDB & X-Engine: A hybrid engine deployment of InnoDB and X-Engine. If you select this option, you can set the proportion of storage for X-Engine. For more information, see X-Engine.
   Storage Billing Method	You can select Pay by Used Capacity (Pay-as-you-go) or Subscription. Pay by Used Capacity (Pay-as-you-go): You are charged only for the storage you use. Storage capacity automatically scales with your data, so you do not need to specify a capacity at purchase. Subscription: You prepay for a specific amount of storage capacity when you purchase the cluster. Note This parameter is available only when the cluster billing method is set to Subscription.
   Storage Capacity	Configure the amount of storage capacity to purchase. Note This parameter needs to be configured only in the following cases: The storage type is ESSD cloud disk. The cluster billing method is Subscription, and the Storage Billing Method is Subscription.

3. (Optional) Advanced options:

   Parameter	Description
   Cluster Name	Set a name for the cluster. You can customize the name based on your business requirements. If you do not specify a name, the system automatically generates one. You can modify the cluster name at any time after the cluster is created. The cluster name must meet the following requirements: It cannot start with http:// or https://. It must be 2 to 256 characters in length.
   Resource Group	Select a target resource group from the list of created resource groups. Note A resource group is a container that is used to manage a group of related resources under a single Alibaba Cloud account. A resource can belong to only one resource group. For more information, see Resource groups and authorization.
   Parameter Template	Set the parameter template for the cluster. You can select a system-provided template or a custom one. Note The drop-down list displays all custom and system-default parameter templates in the current region.
   Time Zone	Set the time zone for the cluster. The default is UTC+08:00.
   Table name case sensitivity	Specify whether table names in the cluster are case-sensitive. By default, they are not. Note If your on-premises database is case-sensitive, we recommend that you select Case-sensitive for consistency to facilitate data migration. This setting cannot be changed after the cluster is created. Choose this option with caution.
   Backup retention policy on deletion	Set the backup retention policy for when the cluster is deleted (released). Retain Last Automatic Backup (Automatic Backup Before Release) (Default): When the cluster is released, the last backup is kept in the cluster recycle bin, and you will be charged for it. Retain All Backups: When the cluster is released, all backups are kept in the cluster recycle bin, and you will be charged for them. Delete All Backups (Cannot Be Restored): When the cluster is released, it is permanently deleted. The data is not retained and cannot be recovered. No fees are charged.
   Enable TDE	You can directly enable transparent data encryption (TDE) without having to enable it separately after the cluster is created. Note TDE cannot be disabled after it is enabled. TDE relies on Key Management Service (KMS). After you enable TDE, you must configure a service-linked role to authorize PolarDB to access KMS. After TDE is enabled, PolarDB encrypts the cluster's data files. This process is transparent to your applications but can result in a performance loss of 5% to 10%.

4. On the right side of the page, confirm the quantity and cluster configuration, then complete the purchase.

   Parameter	Description
   Quantity	Select the number of clusters to purchase. Note You can create up to 50 clusters at a time. This is useful for scenarios that require rapid, bulk provisioning, such as launching multiple game servers. You can purchase a maximum of 50 clusters with your Alibaba Cloud account.
   Subscription Duration	Select the subscription duration for the cluster. Note This parameter is available only when the billing method is set to Subscription. This option is not available for pay-as-you-go clusters.
   Auto-renewal	Specify whether to enable auto-renewal. To avoid service disruptions due to a forgotten renewal, we recommend that you enable this feature. Note This parameter is available only when the billing method is set to Subscription. This option is not available for pay-as-you-go clusters. In addition to configuring auto-renewal during purchase, you can also manage this setting later in the Billing Management console.

   Confirm the configuration, total fee, and read the terms of service. Then, click Buy Now.

5. After you complete the purchase, the cluster is created in 10 to 15 minutes. You can then view the new cluster in the cluster list of the PolarDB console.

   Note

   • The cluster is unavailable while its status is Creating. It is ready for use when the status changes to Running.

   • Ensure you have selected the correct region to see your new cluster.

Next steps

Connect to a database

FAQ

Related APIs

In addition to using the console, you can create clusters by calling an API. The following table lists the relevant APIs.