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    Key Management Service:Purchase and enable a KMS instance

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    Key Management Service:Purchase and enable a KMS instance

    Last Updated:Mar 20, 2025

    Key Management Service (KMS) instances provide key-related and secret-related features. You can use keys to encrypt and decrypt sensitive data. You can use secrets to reduce risks that are caused by hardcoded secrets in code. This helps improve data security. This topic describes how to purchase and enable a KMS instance.

    Overview

    Before you purchase a KMS instance, make sure that you are familiar with the specifications of KMS instances and the business components of KMS. Then, you can select appropriate specifications based on your business scenarios and security compliance requirements. For more information, see Instance selection.

    Step 1: Purchase a KMS instance

    1. Log on to the KMS console. In the top navigation bar, select a region. In the left-side navigation pane, choose Resource > Instances.

    2. On the Instances page, click Create Instance. In the Create Instance dialog box, select a billing method. On the buy page, configure the parameters and click Buy Now.

      Parameter

      Description

      Site

      The site on which you want to deploy the KMS instance. Valid values: Regions Outside Chinese Mainland and Regions in Chinese Mainland.

      Instance Type

      The type of the KMS instance. Valid values:

      • Software Key Management: allows you to create a key store. You can manage the lifecycles of keys and use keys for encryption and decryption.

      • Hardware Key Management: allows you to manage keys that are stored in a hardware security module (HSM) cluster and helps you quickly build a key management center in the cloud.

      • Value-added Plan: provides expert services, the instance backup feature, and the default key rotation feature. For more information, see Backups and Configure key rotation.

      Region

      The region of the KMS instance. For more information, see Supported regions.

      Deployment Mode

      KMS instances support dual-zone or multi-zone configurations to achieve high availability, disaster recovery, and load balancing.

      Note

      • Philippines (Manila) and Thailand (Bangkok) provide only a single zone, so the KMS instance can only be deployed in a single zone. In this case, the default deployment mode is single zone.

      • When you select multi-zone, you can configure up to three zones.

      For the number of zones in each region, see Regions and access addresses.

      Computing Performance

      The computing performance of the KMS instance. For more information, see Performance data.

      If the provided computing performance of KMS instances of the software key management type on the buy page cannot meet your business requirements, contact us for the computing performance of 10,000 QPS or 20,000 QPS.

      Number of Keys

      The maximum number of keys that can be created in the KMS instance.

      Number of Secrets

      The maximum number of secrets that can be created in the KMS instance.

      Access Management Quantity

      The quota of objects that are allowed to access the KMS instance. The quota includes the number of Alibaba Cloud accounts that use the resources of the KMS instance and the number of virtual private clouds (VPCs) that are associated with the KMS instance. Default value: 1.

      For example, if the KMS instance needs to be associated with three VPCs and shared with two Alibaba Cloud accounts, specify a value no less than 5 for the parameter to meet your business requirements.

      Log Analysis

      Specifies whether to enable the log analysis feature. For more information, see Overview of Simple Log Service for KMS.

      Log Storage Capacity

      The storage capacity for logs, with a minimum allocation of 1,000 GB. The capacity increases in increments of 1,000 GB. For more information about how to evaluate the storage capacity, see Overview of Simple Log Service for KMS.

      Purchase quantity

      The number of KMS instances that you want to purchase.

      Important

      In most cases, you need to purchase only one KMS instance. If you want to purchase more than one KMS instance, contact us.

      Duration

      The subscription duration of the KMS instance.

      Note

      You can select Auto-renewal to automatically renew the KMS instance when the instance expires.

    3. Read and select Terms of Service, and click Pay to complete the payment.

      The system requires 1 to 5 minutes to create the KMS instance. You can view the created instance on the Instances page.

    Step 2: Enable the KMS instance

    After purchasing a KMS instance, enable it by associating it with a virtual private cloud (VPC) and vSwitch. This network configuration provides secure access for managing cryptographic resources within the instance, including key and secrets management, encryption, and decryption.

    The supported KMS instance types are software, hardware and external key management instances.

    Software key management instance

    Prerequisites

    • When you purchase a KMS instance under the following conditions, Private DNS (a new form of Alibaba Cloud DNS PrivateZone) must be activated:

      • Using an International site (alibabacloud.com) account within the Chinese mainland.

      • Using a China site (aliyun.com) account outside the Chinese mainland.

    Note

    • Private DNS is automatically activated without additional configuration under other purchase conditions.

    • KMS covers the domain name resolution fees. You do not need to pay for them in Private DNS.

    Procedure

    Console

    1. Log on to the KMS console. In the top navigation bar, select a region. In the left-side navigation pane, choose Resource > Instances.

    2. On the Software Key Management tab, find the KMS instance that you want to enable and click Enable in the Actions column.

    3. In the Enable KMS Instance panel, configure the parameters and click Enable Now.

      Important

      Specify the correct VPC ID when enabling your KMS instance. You cannot modify it after the instance is enabled.

      Parameter description

      Parameter

      Description

      Instance Name

      Specify a name for the KMS instance. It supports letters, digits, and the following special characters: _/+=.@-.

      VPC ID

      Specify the VPC ID associated with your KMS instance. This ID cannot be modified after enabling the instance.

      Zone Configuration

      Set the zone and associated vSwitch for the instance. The number of zones depends on your purchase option:

      • Subscription: Supports dual-zone and multi-zone deployments. If you selected multi-zone during purchase, you can configure up to three zones.

      • Pay-as-you-go: Defaults to a dual-zone setup.

      Single-zone regions

      Specific regions provide only a single zone, such as Thailand (Bangkok). In these regions, the KMS instance will be automatically configured for a single zone.

      • Zone and vSwitch Configuration: Configure a zone and associated vSwitch. Make sure that the vSwitch has at least one available IP address. KMS requires this IP to access your network.

      • Other Zones: Select Randomly Assign or Manually Specify.

    Wait for approximately 30 minutes and then refresh the page. If the status of the KMS instance changes to Enabled, the KMS instance is enabled.

    API

    Call the ConnectKmsInstance operation.

    Terraform

    For instructions, see Purchase and enable a software key management instance with Terraform.

    Hardware key management instance

    Prerequisites

    • A connected Cloud Hardware Security Module (HSM) cluster is available for the KMS instance. Configure an HSM cluster.

      The region of the cluster and the hardware key management instance must be the same.

      Warning

      To increase the number of HSMs in the HSM cluster in subsequent operations, contact Alibaba Cloud technical support to change the cluster synchronization method to automatic synchronization. This prevents cluster synchronization failures.

    • Network setting: Each zone requires one vSwitch with at least four available IP addresses for the KMS instance.

      For a dual-zone deployment, choose one of the following options:

      • (Recommended) Use the two vSwitches that are bound to your HSM.

        You do not need to create vSwitches. Just ensure each one has at least four available IP addresses.

      • Do not use the two vSwitches that are bound to your HSM.

        Create two vSwitches in different zones for network planning flexibility. Ensure that four available IP addresses are reserved for each vSwitch.

      To view the number of available IP addresses on a vSwitch, log on to the VPC console, and click the vSwitch ID on the vSwitch page.

      Why four available IP addresses: In dual-zone KMS deployments, each HSM in the cluster requires two IP addresses for its highly available Elastic Network Interface (ENI) pair. So, to host two HSMs in a zone, four IP addresses are needed for each vSwitch.

    • When you purchase a KMS instance under the following conditions, Private DNS (a new form of Alibaba Cloud DNS PrivateZone) must be activated:

      • Using an International site (alibabacloud.com) account within the Chinese mainland.

      • Using a China site (aliyun.com) account outside the Chinese mainland.

    Note

    • Private DNS is automatically activated without additional configuration under other purchase conditions.

    • KMS covers the domain name resolution fees. You do not need to pay for them in Private DNS.

    Procedure

    Hardware key management instances can only be enabled through the console.

    1. Log on to the KMS console. In the top navigation bar, select a region. In the left-side navigation pane, choose Resource > Instances.

    2. On the Hardware Key Management tab, find the KMS instance that you want to enable and click Enable in the Actions column.

    3. In the Connect to HSM panel, specify an HSM cluster and click Connect to HSM.

      To specify an HSM cluster, you must configure the following parameters.

      Parameter

      Description

      Instance Name

      Specify a name for the KMS instance. It supports letters, digits, and the following special characters: _/+=.@-.

      Configure HSM Cluster

      Select the HSM cluster that you created.

      Note

      You can connect a hardware key management instance to only one HSM cluster.

      Configure HSM Access Secret.

      • Username: the username of the crypto user. The value is fixed as kmsuser.

      • Password: the password of the crypto user. Enter the password that you specified when you created the crypto user.

      • Security Domain Certificate: a root certification authority (CA) certificate in the PEM format. To obtain the certificate, perform the following operations: Log on to the Cloud Hardware Security Module console. Click one HSM ID in the cluster. On the Details page, find ClusterOwnerCertificate, which is the Security Domain Certificate. Copy the content of the Security Domain Certificate or save it in PEM format, then upload it.

      VPC ID

      By default, the ID of the VPC that is associated with the HSM is used. You cannot modify this default ID.

      Zone and vSwitch Configuration

      Set the zone and associated vSwitch for the instance. The deployment modes are dual-zone and multi-zone. If you selected multi-zone, you can configure up to three zones. Make sure that at least four available IP addresses are reserved for each vSwitch in a zone.

      The enablement time for the KMS instance depends on whether you configured the Number of Secrets parameter during purchase. Refresh the page to monitor the status. The KMS instance is enabled when its status displays Enabled.

      • With Number of Secrets: ~30 minutes.

      • Without Number of Secrets: ~10 minutes.

    External key management instance

    Prerequisites

    • A hardware security module outside the cloud is purchased, and an external key instance (XKI) proxy is configured. For instructions, contact your HSM provider.

    • If you want to use a VPC endpoint service to connect to KMS, you must first create a VPC endpoint service. Note the following:

      • The endpoint service zones match your KMS instance zones.

      • The current Alibaba Cloud account must be added to the endpoint service whitelist.

      • Automatically Accept Endpoint Connections is set to Yes.

      Alternatively, if you do not want to use VPC Endpoint Service, KMS supports connections to the XKI proxy by using a public endpoint.

    • When you purchase a KMS instance under the following conditions, Private DNS (a new form of Alibaba Cloud DNS PrivateZone) must be activated:

      • Using an International site (alibabacloud.com) account within the Chinese mainland.

      • Using a China site (aliyun.com) account outside the Chinese mainland.

    Note

    • Private DNS is automatically activated without additional configuration under other purchase conditions.

    • KMS covers the domain name resolution fees. You do not need to pay for them in Private DNS.

    Procedure

    External key management instances can only be enabled through the console.

    1. Log on to the KMS console. In the top navigation bar, select a region. In the left-side navigation pane, choose Resource > Instances.

    2. Click the External Key Management tab, find the instance that you want to enable, and then click Enable in the Actions column.

    3. In the Connect to HSM panel, configure parameters and click Connect to HSM.

      Parameter

      Description

      Instance Name

      Specify a name for the KMS instance. It supports letters, digits, and the following special characters: _/+=.@-.

      VPC ID

      Specify the VPC ID associated with your KMS instance. This ID cannot be modified after enabling the instance.

      Zone Configuration

      Set the zone and associated vSwitch for the instance. The deployment modes are dual-zone and multi-zone. If you select multi-zone, you can configure up to three zones.

      Single-zone regions

      Specific regions provide only a single zone, such as Thailand (Bangkok). In these regions, the KMS instance will be automatically configured for a single zone.

      • Zone and vSwitch Configuration: Configure a zone and vSwitch. Make sure that the vSwitch has at least one available IP address. KMS requires this IP to access your network.

      • Other Zones: Select Randomly Assign or Manually Specify.

      External Proxy Connectivity

      • Public Endpoint Connectivity: The KMS instance connects to the XKI proxy by using a public endpoint over the Internet.

      • VPC Endpoint Service Connectivity : The KMS instance connects to the XKI proxy by using a VPC endpoint service.

      Domain Name of External Proxy

      If you set External Proxy Connectivity to Public Endpoint Connectivity, enter the domain name of your XKI proxy.

      Endpoint Service

      If you set External Proxy Connectivity to VPC Endpoint Service Connectivity , select an endpoint service.

      The two zones of the endpoint service must be the same as those that you select when you enable the KMS instance.

      External Proxy Configuration

      • Manual Configuration: You must configure External Proxy Path, Certificate Fingerprint, AccessKey ID, and AccessKey Secret. Enter the AccessKey ID and AccessKey secret of the XKI proxy.

      • Configuration File Upload: You can upload a configuration file.

      The enablement time for the KMS instance depends on whether you configured the Number of Secrets parameter during purchase. Refresh the page to monitor the status. The KMS instance is enabled when its status displays Enabled.

      • With Number of Secrets: ~30 minutes.

      • Without Number of Secrets: ~10 minutes.

    FAQs

    References