# Creating a lifecycle policy preview in Amazon ECR
Creating a lifecycle policy preview

You can use a lifecycle policy preview to see the impact of a lifecycle policy on an image repository before you apply it. It is considered best practice to do a preview before applying a lifecycle policy to a repository.

**Note**  
If you are using Amazon ECR replication to make copies of a repository across different Regions or accounts, note that a lifecycle policy can only take an action on repositories in the Region it was created in. Therefore, if you have replication turned on you may want to create a lifecycle policy in each Region and account you are replicating your repositories to.

**To create a lifecycle policy preview (AWS Management Console)**

1. Open the Amazon ECR console at [https://console.aws.amazon.com/ecr/repositories](https://console.aws.amazon.com/ecr/repositories).

1. From the navigation bar, choose the Region that contains the repository on which to perform a lifecycle policy preview.

1. In the navigation pane, under **Private registry**, choose **Repositories**.

1. On the **Private repositories** page, select a repository and that use the **Actions** drop down to choose **Lifecycle policies**.

1. On the lifecycle policy rules page for the repository, choose **Edit test rules**, **Create rule**.

1. Specify the following details for each test lifecycle policy rule.

   1. For **Rule priority**, type a number for the rule priority. The rule priority determines in what order the lifecycle policy rules are applied. A lower number means higher priority. For example, a rule with priority 1 takes precedence over a rule with priority 2.

   1. For **Rule description**, type a description for the lifecycle policy rule.

   1. For **Image status**, choose **Tagged (wildcard matching)**, **Tagged (prefix matching)**, **Untagged**, or **Any**.
**Important**  
If you specify multiple tags, only the images with all specified tags are selected.

   1. If you chose **Tagged (wildcard matching)** for **Image status**, then for **Specify tags for wildcard matching**, you can specify a list of image tags with a wildcard (**\$1**) on which to take action with your lifecycle policy. For example, if your images are tagged as `prod`, `prod1`, `prod2`, and so on, you would specify `prod*` to take action on all of them. If you specify multiple tags, only the images with all specified tags are selected.
**Important**  
There is a maximum limit of four wildcards (`*`) per string. For example, `["*test*1*2*3", "test*1*2*3*"]` is valid but `["test*1*2*3*4*5*6"]` is invalid.

   1. If you chose **Tagged (prefix matching)** for **Image status**, then for **Specify tags for prefix matching**, you can specify a list of image tags on which to take action with your lifecycle policy.

   1. For **Match criteria**, choose **Days since image created**, **Days since last recorded pull time**, **Days since image archived**, or **Image count** and then specify a value.

   1. For **Rule action**, choose either **Expire** or **Archive**.

   1. Choose **Save**.

1. Create additional test lifecycle policy rules by repeating steps 5–7.

1. To run the lifecycle policy preview, choose **Save and run test**.

1. Under **Image matches for test lifecycle rules**, review the impact of your lifecycle policy preview.

1. If you are satisfied with the preview results, choose **Apply as lifecycle policy** to create a lifecycle policy with the specified rules. You should expect that after applying a lifecycle policy, the affected images are expired or archived within 24 hours.

1. If you aren't satisfied with the preview results, you may delete one or more test lifecycle rules and create one or more rules to replace them and then repeat the test.