# Adding a scaling policy
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You can add a scaling policy using the Amazon Web Services Management Console. 

**To add an Auto Scaling policy to an ElastiCache for Valkey and Redis OSS cluster**

1. Sign in to the Amazon Web Services Management Console and open the Amazon ElastiCache console at [https://console.amazonaws.cn/elasticache/](https://console.amazonaws.cn/elasticache/).

1. In the navigation pane, choose **Valkey** or **Redis OSS**. 

1. Choose the cluster that you want to add a policy to (choose the cluster name and not the button to its left). 

1. Choose the **Auto Scaling policies** tab. 

1. Choose **add dynamic scaling**. 

1. For **Policy name** enter a policy name. 

1. For **Scalable Dimension** choose **shards**. 

1. For the target metric, choose one of the following:
   + **Primary CPU Utilization** to create a policy based on the average CPU utilization. 
   + **Memory** to create a policy based on the average database memory. 
   + **Capacity** to create a policy based on average database capacity usage. The Capacity metric includes memory and SSD utilization for data-tiered instances, and memory utilization for all other instance types.

1. For the target value, choose a value greater than or equal to 35 and less than or equal to 70. Auto scaling will maintain this value for the selected target metric across your ElastiCache shards: 
   + **Primary CPU Utilization**: maintains target value for `EngineCPUUtilization` metric on primary nodes. 
   + **Memory**: maintains target value for `DatabaseMemoryUsageCountedForEvictPercentage` metric 
   + **Capacity** maintains target value for `DatabaseCapacityUsageCountedForEvictPercentage` metric,

   Cluster shards are added or removed to keep the metric close to the specified value. 

1. (Optional) Scale-in or scale-out cooldown periods are not supported from the console. Use the Amazon CLI to modify the cooldown values. 

1. For **Minimum capacity**, type the minimum number of shards that the ElastiCache Auto Scaling policy is required to maintain. 

1. For **Maximum capacity**, type the maximum number of shards that the ElastiCache Auto Scaling policy is required to maintain. This value must be less than or equal to 250.

1. Choose **Create**.