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

Prerequisites

You have an Alibaba Cloud account. For instructions, see Register and log on 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 the 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	Regions 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 nearby region. The region cannot be changed after purchase. (Recommended) Create your PolarDB cluster in the same region as the ECS instances that need to connect to it. Otherwise, they cannot communicate over the internal network and can communicate only over the public network, which prevents the cluster from delivering optimal 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 What Is 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. During the migration, the system automatically synchronizes the accounts, databases, IP address whitelist, and necessary parameter configurations of the RDS instance. You can also retain the original database endpoint to simplify migration and support a smooth business transition. For more information, see Solution overview. Note The list of available RDS instances excludes read-only instances and instances that use non-InnoDB engines. Clone from RDS: Based on the selected RDS instance, you can quickly clone a PolarDB cluster with the exact same data. This creation method does not synchronize incremental data from the RDS instance to the PolarDB cluster. For more information, see Clone an ApsaraDB RDS for MySQL instance to a PolarDB for MySQL cluster with one click. Note The list of available RDS instances excludes read-only instances and instances that use non-InnoDB engines. Restore From Recycle Bin: Uses the cluster backup sets retained in the Cluster recycle bin overview to restore a deleted PolarDB cluster. Note If the original PolarDB cluster had What Is X-Engine enabled and the corresponding database and table data exists, you must set the Storage engine parameter to InnoDB & X-Engine. 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 Engine version. For more information, see Feature comparison of PolarDB for MySQL 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 Differences between Enterprise Edition and Standard Edition.
   Edition	Enterprise Edition supports two series: Cluster Edition and Multi-master Cluster (Limitless) Edition. This option is not available for Standard Edition. Note The two series have different architectures and use cases. For more information, see Enterprise editions.
   Specification Edition	You can select a Dedicated or a General-purpose specification type: Dedicated: 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: Different clusters on the same server make full use of each other's idle computing resources, such as CPU. This resource sharing delivers economies of scale and better cost-effectiveness. For a detailed comparison of the two specification types, see Comparison between general-purpose and dedicated compute nodes.
   CPU Architecture	You can select X86 or ARM. x86: The x86 architecture uses Intel processors with high-performance network infrastructure, providing comprehensive improvements in overall performance and stability to meet the requirements of enterprise applications that demand high stability and computing power. Arm: The Arm architecture uses Alibaba Cloud's self-developed Yitian 710 processor chips and 25 GE smart high-speed network interface cards (NICs) to provide powerful computing capabilities. The high-performance network infrastructure better meets the requirements of government agencies, Internet companies, and other enterprises for cost-effectiveness, security, and stability. Note Enterprise Edition has a CPU architecture fixed to X86.
   Primary Zone	Zones 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. (Recommended) Select the same VPC as the ECS instances that need to connect to the cluster. Otherwise, they cannot communicate over the internal network and can communicate only over the public 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 have not created a VPC that meets your network requirements, 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	(Recommended) Select Enable. Add the CIDR block of your selected VPC to the PolarDB cluster's whitelist so that ECS instances in the same VPC can 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	Only when the Billing type is Serverless can you set the resource scaling range of a Serverless cluster: Minimum Read-only Nodes: Set the minimum number of read-only nodes that can be added. Valid values: 0 to 15. Maximum Read-only Nodes: Set the maximum number of read-only nodes that can be added. Valid values: 0 to 15. Note The number of read-only nodes automatically increases or decreases within the lower and upper limits that you set, based on the actual workload. For details about the scaling policy, see Scaling. (Recommended) To ensure high availability of the serverless cluster, set Minimum Read-only Nodes to 1. Minimum PCUs per Node: Set the lower limit for the number of PCUs for each node in the cluster. Valid values: 0.25 PCU to 31 PCUs. Maximum PCUs per Node: Set the upper limit for the number of PCUs for each node in the cluster. Valid values: 1 PCU to 32 PCUs. Note PCUs are the unit for second-level billing and resource scaling for the serverless feature. One PCU is approximately equal to 1 core and 2 GB of memory. The PCUs of a node is dynamically adjusted within the specified range based on the workloads. The minimum granularity for scaling is 0.5 PCUs. Example: If you set Minimum PCUs per Node to 2 PCUs and Maximum PCUs per Node to 16 PCUs, the default specification of the primary node and the read-only nodes in the serverless cluster is 2 PCUs (approximately 2 cores and 4 GB of resources). When the system detects an increase in workload, it automatically increases the number of PCUs of the primary node or the read-only nodes. Based on your settings, the number can increase to a maximum of 16 PCUs (approximately 16 cores and 32 GB of resources).
   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	When you create a PolarDB cluster, you can Enable serverless for fixed-specification clusters. When enabled, the cluster can dynamically scale resources based on the workload, in addition to the fixed specifications of the selected compute nodes. However, this incurs corresponding scale-up fees. Note By default, the Serverless configuration provides a single-node elasticity range of 0 to 8 and a read-only node range of 0 to 1. At any time afterward, you can use the cluster details page to adjust these configuration parameters.
   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, when you purchase a cluster, you can set Read-only Node to 0 to purchase a single-node PolarDB cluster. 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. You can then migrate the data from the original cluster to the new cluster by using a migration tool such as DTS or the major version upgrade feature. Node types: Primary Node: Handles write operations and some read operations. The primary node and read-only nodes use an active-active failover mechanism to provide high availability for the database. Read-only Node: Handles read operations to offload the primary node, and provides high availability and scalability. After the cluster is created, based on your business needs, you can dynamically adjust the number of read-only nodes. Read-only IMCI Node: A functional node for the What is In-Memory Column 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 a read-only IMCI 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 are then automatically routed to read-only row-based nodes or read-only column-based nodes instead of being sent to 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 sub-series specification. General-purpose clusters use Standard Enterprise Edition, while Dedicated clusters use Dedicated Enterprise Edition. The PolarProxy specification can be configured separately, with options ranging from 4C to 16C (that is, 4 vCPUs to 16 vCPUs). (Recommended) Select automatic matching. Note This parameter can be configured only for Standard Edition clusters.
   Storage Type	PolarDBThe supported storage types are ESSD cloud disks, PSL4, and PSL5. ESSD cloud disks are available only for Standard Edition clusters. ESSD cloud disks are a new generation of ultra-high-performance disk products from Alibaba Cloud. ESSDs are built on a new-generation distributed block storage architecture, combined with 25 GE networks and RDMA technology, providing up to 1 million random read/write IOPS and lower one-way latency per disk. ESSDs are divided into the following categories: 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 workloads that require extremely high concurrent I/O performance and extremely stable read/write latency. AutoPL ESSD: Compared with PL0, PL1, PL2, and PL3 ESSDs, AutoPL ESSDs decouple IOPS from capacity, which allows flexible configuration and on-demand adjustment. This reduces the overall total cost of ownership (TCO). Important For more information about the performance of ESSD cloud disks, see ESSDs. After the storage space of an ESSD cloud disk is full, the disk is locked and 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	The supported engine types are InnoDB and 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 X-Engine proportion. For more information, see What Is X-Engine.
   Storage Billing Method	The supported storage billing types are Pay by Used Capacity (Pay-as-you-go) and Subscription. Pay by Used Capacity (Pay-as-you-go): You do not need to specify a capacity at purchase. Storage capacity automatically scales online as your data grows, and you are charged only for the storage space that your actual data occupies. Subscription: You prepay for the storage capacity of the cluster when you purchase the database cluster. Note This option is available only when the Billing type 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. Billing type is set to Subscription, and the Storage Billing Method is set to Subscription.

3. (Optional) Advanced options:

   Parameter	Description
   Cluster Name	Set a name for the cluster. You can customize the cluster 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 existing resource groups. For more information, see Create a resource group. 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 Manage permissions with resource groups.
   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 of the cluster. The default time zone is UTC+08:00.
   Table name case sensitivity	Specify whether table names in the cluster are case-sensitive. By default, table names are not case-sensitive. Note If your on-premises database is case-sensitive, select Case-sensitive to stay consistent with your on-premises database and simplify data migration. This setting cannot be changed after the cluster is created. Choose this option with caution.
   When the cluster is deleted (released)	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 deleted (released), the last backup is kept in the Cluster recycle bin overview, and you are charged for it. Retain All Backups: When the cluster is deleted (released), all backups are kept in the Cluster recycle bin overview, and you are charged for them. Delete All Backups (Cannot Be Restored): The cluster is permanently deleted when it is deleted (released). 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 role. For more information, see Authorize PolarDB to access KMS. After TDE encryption is enabled, PolarDB encrypts the data files of the cluster. This process is transparent to your applications but causes a performance loss of 5% to 10%.

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

   Parameter	Description
   Quantity	Select the number of clusters to purchase. Note You can create up to 50 clusters at a time. This is suitable for use cases such as launching multiple game servers at once. 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 can be configured only when the Billing type is set to Subscription. Pay-as-you-go clusters do not have this option.
   Auto-renewal	Specify whether to enable auto-renewal. To avoid service interruptions caused by a forgotten renewal, enable auto-renewal. Note This parameter can be configured only when the Billing type is set to Subscription. Pay-as-you-go clusters do not have this option. In addition to configuring auto-renewal when you purchase the cluster, you can also configure it in the Expenses and Costs console.

   After you configure the preceding parameters, confirm the cluster configuration and the actual fee, and read the terms of service on the page. If everything is correct, click Buy Now.

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

   Note

   • While the status of the nodes in the cluster is Creating, the cluster may still be under creation and is unavailable. The cluster can be used only when the cluster status is Running.

   • Make sure that you have selected the correct region in the upper-left corner of the page. Otherwise, you cannot view the cluster that you created.

Next steps

How to connect to a Database

FAQ

Related APIs

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