Elastic Compute Service:Configure a private pool for an existing instance

Use cases

• Free up pool capacity for new instances: Remove instances from a private pool to free capacity for creating new instances when resources are constrained.

• Apply a pool to running instances: Associate running instances with a private pool from a capacity reservation to improve utilization.

• Unblock a capacity reservation purchase: If a capacity reservation purchase is rejected due to insufficient resources, set the private pool type of existing instances to Open. The instances then count as matchable resources, allowing the purchase to succeed.

Prerequisites

• A pay-as-you-go ECS instance. Subscription instances do not support private pool configuration.

Procedure

1. Go to the Instances page of the ECS console.

2. In the top navigation bar, select the region and resource group.

3. Click the instance ID. On the Instance Details tab, click All Actions, then search for and click Configure Private Pool.

4. In the Configure Private Pool dialog box, set Private Pool Type:

   Private Pool Type	Behavior
   Target	Uses a specific private pool. Enter the ID of a dedicated or open private pool. The ID corresponds to an elastic assurance or immediate capacity reservation.
   Open	Matches an open private pool. If tags on the instance match those of an elastic assurance or capacity reservation, the instance uses the corresponding open private pool. If no tags are attached, the system selects an untagged open private pool.
   None	Removes the instance from all private pools. The instance uses only the public pool.

   Important

   Removing an instance from a private pool may reduce the pool's capacity if the system lacks inventory to replenish it. This applies when you change from Target to Open, or from Target or Open to None.

5. Click Confirm.

Tag matching and rematch behavior

To trigger a rematch for an instance that already matches an open private pool by tag, do one of the following:

• Modify the tags of the instance.

• Enable economical mode for the instance.

• Stop and then start the instance.

ID takes precedence over tags

If you specify an open private pool ID and attach tags that match a different pool, the specified ID takes precedence. For example, if you enter the ID of pool A and attach tags matching pool B, the instance uses pool A.

Verify the configuration

On the Instance Details tab, check the Private Pool field in the Other Information section. See View a private pool.