When you purchase an immediate capacity reservation, you must specify attributes such as instance type, zone, and operating system. Alibaba Cloud reserves resources that have matching attributes in a private pool for your use to create pay-as-you-go instances.

Background information

An immediate capacity reservation begins to be billed at the pay-as-you-go instance rate of the specified instance type as soon as the capacity reservation is purchased, regardless of whether it is used to create pay-as-you-go instances. Billing continues until the capacity reservation is manually released or automatically released on expiration.
Note Before the capacity reserved by an immediate capacity reservation is used to create pay-as-you-go instances, you are charged only for the instance type. After the capacity reserved by the capacity reservation is used to create pay-as-you-go instances, you are charged based on instance configurations including the instance type, disks, and public bandwidth. For more information about billing rules, see Pay-as-you-go.

Procedure

  1. Log on to the ECS console.
  2. In the left-side navigation pane, choose Instances & Images > Resource Assurance.
  3. In the top navigation bar, select a region.
  4. In the upper part of the Resource Assurance page, click the Capacity Reservation tab.
  5. Click Purchase Capacity Reservation.
  6. In the Query Solutions step, configure parameters and click Next: Confirm Information.
    1. Configure the attributes of the immediate capacity reservation.
      A capacity reservation can be used to create only pay-as-you-go instances that match the attributes of the capacity reservation, such as instance type, zone, and operating system. The following table describes parameters used to specify the attributes of a capacity reservation.
      Parameter Description
      Application Mode Only a value of Effective Immediately is available.
      Expiration Method After an immediate capacity reservation is released, instances that are using its associated private pool are not affected and the unused reserved capacity is no longer billed. Valid values:
      • Manual Release: After you purchase the immediate capacity reservation, it exists until you manually release it.
      • Release Upon Expiration: The immediate capacity reservation is automatically released when it expires. If you select Release Upon Expiration, you must set Expired At to specify an expiration time for the capacity reservation. The expiration time must be more than 1 hour later than the current time.
      Billing Method After an immediate capacity reservation is purchased, you can use the reserved capacity in the associated private pool to create only pay-as-you-go instances.
      Region and Zone Specify the region and zone in which to reserve resources. In the Recommended Solution section, other zones may be recommended based on resource availability. The zone in the solution that you select is used.
      Instance Type Specify the instance type for which to reserve resources. In the Recommended Solution section, other alternative instance types may be recommended based on resource availability. The instance type in the solution that you select is used.
      Operating System Specify the operating system type for instances. Valid values: linux and windows. If you want to use an immediate capacity reservation in conjunction with a regional reserved instance to reduce costs, make sure that their operating system types are the same.
      Reserved Quantity Specify the number of instances for which to reserve resources.
    2. View and select a solution in the Recommended Solution section.
      The recommended solutions may deliver optimal performance, be backed by the most sufficient supply of resources, or provide multi-zone disaster recovery. You can select the solution that best suits your needs. ea-recommended
      Note If no recommended solutions are available or if the recommended solutions cannot meet your requirements, you can submit a ticket.
    3. Configure the private pool.
      After an immediate capacity reservation is purchased, Alibaba Cloud reserves resources that match the attributes (such as instance type, zone, and operating system) of the capacity reservation in a private pool.
      Parameter Description
      Private Pool Type The private pool type. Valid values: Open and Targeted.
      • You can use one of the following methods to specify which open private pool to use:
        • Specify the ID of an open private pool to use when you create instances.
        • If tag matching is enabled for an open private pool, you can add the tags of the associated capacity reservation when you create instances to use the open private pool.
        • If tag matching is not enabled for one or more open private pools and you select Open as the private pool type without specifying a private pool ID, the system selects for you an open private pool whose associated capacity reservation does not have tags.
      • To use a targeted private pool to create instances, you must manually specify the ID of the private pool.

      We recommend that you prepare a number of open and targeted private pools based on your business types. For example, you can prepare targeted private pools dedicated to key business. For more information, see Private Pool.

      Private Pool Name The name of the private pool. The name must be 2 to 128 characters in length and can contain letters, digits, colons (:), underscores (_), periods (.), and hyphens (-). It must start with a letter and cannot start with http:// or https://.
      Description The description of the private pool. Enter an informative description for easy management. The description must be 2 to 256 characters in length and cannot start with http:// or https://.
    4. Add tags.
      You can perform operations such as batch executing O&M tasks and financial sharing based on tags. For more about the use scenarios of tags and how to work with tags, see Overview.
      In addition to common use scenarios, you can use open private pools in a fine-grained manner based on tags. After you add tags to an immediate capacity reservation, tag matching is automatically enabled for the associated private pool. If you select Open as the private pool type and add the same tags when you create instances, the associated private pool is automatically matched and used.
      Notice After an immediate capacity reservation takes effect, its associated private pool is always matched based on the tags added when the capacity reservation was purchased. We recommend that you do not edit the tags of purchased immediate capacity reservations.
  7. In the Confirm Information step, confirm you configurations, click Purchase, and then complete the payment.
    1. View the parameters in the Capacity reservation overview.
    2. Select one or more capacity reservations in the Capacity reservation split section.
      Each capacity reservation is applicable only to a specific instance type within a specific zone. If you select a solution that includes multiple instance types or zones, the solution is automatically split into multiple capacity reservations. Select the capacity reservations that suit your needs.
    3. After you confirm that all configurations are correct, read and select the notes, and then click Purchase.
      Complete the payment as prompted.

What to do next

On the Capacity Reservation tab, view the capacity reservation that you purchased. When the capacity reservation is in the Active state, you can use its associated private pool to create pay-as-you-go instances. For more information, see Use a private pool.