# Examples for creating and managing warm pools with the AWS CLI
You can create and manage warm pools using the AWS Management Console, AWS Command Line Interface (AWS CLI), or SDKs.
The following examples show you how to create and manage warm pools using the AWS CLI.
**Topics**
+ [Example 1: Keep instances in the `Stopped` state](#warm-pool-configuration-ex1)
+ [Example 2: Keep instances in the `Running` state](#warm-pool-configuration-ex2)
+ [Example 3: Keep instances in the `Hibernated` state](#warm-pool-configuration-ex3)
+ [Example 4: Return instances to the warm pool when scaling in](#warm-pool-configuration-ex4)
+ [Example 5: Specify the minimum number of instances in the warm pool](#warm-pool-configuration-ex5)
+ [Example 6: Define the warm pool size using a custom specification](#warm-pool-configuration-ex6)
+ [Example 7: Define an absolute warm pool size](#warm-pool-configuration-ex7)
+ [Example 8: Delete a warm pool](#delete-warm-pool-cli)
## Example 1: Keep instances in the `Stopped` state
The following [put-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/put-warm-pool.html) example creates a warm pool that keeps instances in a `Stopped` state.
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Stopped
```
## Example 2: Keep instances in the `Running` state
The following [put-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/put-warm-pool.html) example creates a warm pool that keeps instances in a `Running` state instead of a `Stopped` state.
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Running
```
## Example 3: Keep instances in the `Hibernated` state
The following [put-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/put-warm-pool.html) example creates a warm pool that keeps instances in a `Hibernated` state instead of a `Stopped` state. This lets you stop instances without deleting their memory contents (RAM).
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Hibernated
```
## Example 4: Return instances to the warm pool when scaling in
The following [put-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/put-warm-pool.html) example creates a warm pool that keeps instances in a `Stopped` state and includes the `--instance-reuse-policy` option. The instance reuse policy value `'{"ReuseOnScaleIn": true}'` tells Amazon EC2 Auto Scaling to return instances to the warm pool when your Auto Scaling group scales in.
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Stopped --instance-reuse-policy '{"ReuseOnScaleIn": true}'
```
## Example 5: Specify the minimum number of instances in the warm pool
The following [put-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/put-warm-pool.html) example creates a warm pool that maintains a minimum of 4 instances, so that there are at least 4 instances available to handle traffic spikes.
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Stopped --min-size 4
```
## Example 6: Define the warm pool size using a custom specification
By default, Amazon EC2 Auto Scaling manages the size of your warm pool as the difference between the maximum and desired capacity of the Auto Scaling group. However, you can manage the size of the warm pool independently from the group's maximum capacity by using the `--max-group-prepared-capacity` option.
The following [put-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/put-warm-pool.html) example creates a warm pool and sets the maximum number of instances that can exist concurrently in both the warm pool and Auto Scaling group. If the group has a desired capacity of 800, the warm pool will initially have a size of 100 as it initializes after running this command.
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Stopped --max-group-prepared-capacity 900
```
To maintain a minimum number of instances in the warm pool, include the `--min-size` option with the command, as follows.
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Stopped --max-group-prepared-capacity 900 --min-size 25
```
## Example 7: Define an absolute warm pool size
If you set the same values for the `--max-group-prepared-capacity` and `--min-size` options, the warm pool has an absolute size. The following [put-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/put-warm-pool.html) example creates a warm pool that maintains a constant warm pool size of 10 instances.
```
aws autoscaling put-warm-pool --auto-scaling-group-name my-asg /
--pool-state Stopped --min-size 10 --max-group-prepared-capacity 10
```
## Example 8: Delete a warm pool
Use the following [delete-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/delete-warm-pool.html) command to delete a warm pool.
```
aws autoscaling delete-warm-pool --auto-scaling-group-name my-asg
```
If there are instances in the warm pool, or if scaling activities are in progress, use the [delete-warm-pool](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/autoscaling/delete-warm-pool.html) command with the `--force-delete` option. This option also terminates the Amazon EC2 instances and any outstanding lifecycle actions.
```
aws autoscaling delete-warm-pool --auto-scaling-group-name my-asg --force-delete
```