# Using a custom Amazon machine image (AMI) in your Elastic Beanstalk environment
This section explains when to consider using a custom AMI and provides the procedures to configure and manage the custom AMI in your environment. When you create an AWS Elastic Beanstalk environment, you can specify an Amazon Machine Image (AMI) to use instead of the standard Elastic Beanstalk AMI included in your platform version. A custom AMI can improve provisioning times when instances are launched in your environment if you need to install a lot of software that isn't included in the standard AMIs.
The use of [configuration files](ebextensions.md) is effective to customize your environment quickly and consistently. Although applying configurations can start to take a long time during environment creation and updates. If you do a lot of server configuration in configuration files, you can reduce this time by making a custom AMI that already has the software and configuration that you need.
A custom AMI also allows you to make changes to low-level components, such as the Linux kernel, that are difficult to implement or take a long time to apply in configuration files. To create a custom AMI, launch an Elastic Beanstalk platform AMI in Amazon EC2, customize the software and configuration to your needs, and then stop the instance and save an AMI from it.
## Creating a custom AMI
You can use [EC2 Image Builder](https://aws.amazon.com/image-builder) to create and manage custom AMIs as an alternative to these procedures. For more information, see the [Image Builder User Guide](https://docs.aws.amazon.com/imagebuilder/latest/userguide/what-is-image-builder.html).
**To identify the base Elastic Beanstalk AMI**
1. In a command window, run a command like the following. For more information, see [describe-platform-version](https://docs.aws.amazon.com/cli/latest/reference/elasticbeanstalk/describe-platform-version.html) in the *AWS CLI Command Reference*.
Specify the AWS Region where you want to use your custom AMI, and replace the platform ARN and version number with the Elastic Beanstalk platform that your application is based on.
**Example - Mac OS / Linux OS**
```
$ aws elasticbeanstalk describe-platform-version --region us-east-2 \
--platform-arn "arn:aws:elasticbeanstalk:us-east-2::platform/Node.js 20 running on 64bit Amazon Linux 2023/6.1.7" \
--query PlatformDescription.CustomAmiList
[
{
"VirtualizationType": "pv",
"ImageId": ""
},
{
"VirtualizationType": "hvm",
"ImageId": "ami-020ae06fdda6a0f66"
}
]
```
**Example - Windows OS**
```
C:\> aws elasticbeanstalk describe-platform-version --region us-east-2 --platform-arn"arn:aws:elasticbeanstalk:us-east-2::platform/
IIS 10.0 running on 64bit Windows Server 2022/2.15.3" --query PlatformDescription.CustomAmiList
[
{
"VirtualizationType": "pv",
"ImageId": ""
},
{
"VirtualizationType": "hvm",
"ImageId": "ami-020ae06fdda6a0f66"
}
]
```
1. Take note of the `ImageId` value that looks like `ami-020ae06fdda6a0f66` in the result.
The value is the stock Elastic Beanstalk AMI for the platform version, EC2 instance architecture, and AWS Region that are relevant for your application. If you need to create AMIs for multiple platforms, architectures or AWS Regions, repeat this process to identify the correct base AMI for each combination.
**Note**
Don't create an AMI from an instance that has been launched in an Elastic Beanstalk environment. Elastic Beanstalk makes changes to instances during provisioning that can cause issues in the saved AMI. Saving an image from an instance in an Elastic Beanstalk environment will also make the version of your application that was deployed to the instance a fixed part of the image.
For Linux, it is also possible to create a custom AMI from a community AMI that wasn't published by Elastic Beanstalk. You can use the latest [Amazon Linux](https://aws.amazon.com/amazon-linux-ami/) AMI as a starting point. When you launch an environment with a Linux AMI that isn't managed by Elastic Beanstalk, Elastic Beanstalk attempts to install platform software (language, framework, proxy server, etc.) and additional components to support features such as [Enhanced Health Reporting](health-enhanced.md).
**Note**
Custom AMIs based on Windows Server require the stock Elastic Beanstalk AMI returned from `describe-platform-version`, as shown earlier in Step 1.
Although Elastic Beanstalk can use an AMI that isn't managed by Elastic Beanstalk, the increase in provisioning time that results from Elastic Beanstalk installing missing components can reduce or eliminate the benefits of creating a custom AMI in the first place. Other Linux distributions might work with some troubleshooting but are not officially supported. If your application requires a specific Linux distribution, one alternative is to create a Docker image and run it on the Elastic Beanstalk [Docker platform](docker.md) or [Multicontainer Docker platform](create_deploy_docker_ecs.md).
**To create a custom AMI**
1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/).
1. Choose **Launch Instance**.
1. If you identified a base Elastic Beanstalk AMI (using `describe-platform-version`) or an Amazon Linux AMI, enter its AMI ID in the search box. Then press **Enter**.
You can also search the list for another community AMI that suits your needs.
**Note**
We recommend that you choose an AMI that uses HVM virtualization. These AMIs show **Virtualization type: hvm** in their description.
For more information, see [Virtualization types](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ComponentsAMIs.html#virtualization_types) in the *Amazon EC2 User Guide*.
1. Choose **Select** to select the AMI.
1. Select an instance type, and then choose **Next: Configure Instance Details**.
1. **(For retired Amazon Linux AMI (AL1) platforms)** Skip this step if your environment runs on a supported Linux-based platform or on a Windows platform.
Expand the **Advanced Details** section and paste the following text in the **User Data** field.
```
#cloud-config
repo_releasever: repository version number
repo_upgrade: none
```
The *repository version number* is the year and month version in the AMI name. For example, AMIs based on the March 2015 release of Amazon Linux have a repository version number `2015.03`. For an Elastic Beanstalk image, this matches the date shown in the solution stack name for your [platform version](concepts.platforms.md) based on Amazon Linux AMI (preceding Amazon Linux 2).
**Note**
The `repo_releasever` setting configures the lock-on-launch feature for an Amazon Linux AMI. This causes the AMI to use a fixed, specific repository version when it launches. This feature isn't supported on Amazon Linux 2—don't specify it if your environment uses a current Amazon Linux 2 platform branch. The setting is required if you're using a custom AMI with Elastic Beanstalk only on Amazon Linux AMI platform branches (preceding Amazon Linux 2).
The `repo_upgrade` setting disables the automatic installation of security updates. It's required to use a custom AMI with Elastic Beanstalk.
1. Proceed through the wizard to [launch the EC2 instance](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/launching-an-instance.html). When prompted, select a key pair that you have access to so that you can connect to the instance for the next steps.
1. [Connect to the instance](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/AccessingInstances.html) with SSH or RDP.
1. Perform any customizations you want.
1. **(Windows platforms)** Run the EC2Config service Sysprep. For information about EC2Config, see [Configuring a Windows Instance Using the EC2Config Service](https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/UsingConfig_WinAMI.html). Ensure that Sysprep is configured to generate a random password that can be retrieved from the AWS Management Console.
1. In the Amazon EC2 console, stop the EC2 instance. Then on the **Instance Actions** menu, choose **Create Image (EBS AMI)**.
1. To avoid incurring additional AWS charges, [terminate the EC2 instance](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/terminating-instances.html).
**To use your custom AMI in an Elastic Beanstalk environment**
1. Open the [Elastic Beanstalk console](https://console.aws.amazon.com/elasticbeanstalk), and in the **Regions** list, select your AWS Region.
1. In the navigation pane, choose **Environments**, and then choose the name of your environment from the list.
1. In the navigation pane, choose **Configuration**.
1. In the **Capacity** configuration category, choose **Edit**.
1. For **AMI ID**, enter your custom AMI ID.
1. To save the changes choose **Apply** at the bottom of the page.
When you create a new environment with the custom AMI, you should use the same platform version that you used as a base to create the AMI.
## Managing an environment with a custom AMI
### Platform updates
When using a custom AMI, Elastic Beanstalk will continue to use the same custom AMI in an environment when its platform version is updated, regardless of whether the update is applied manually or via managed platform updates. The environment will **not** be reset to use the stock AMI of the new platform version.
We recommend that you create a new custom AMI based on the stock AMI of the new platform version. Doing so will apply the patches available in the new platform version and will also minimize deployment failures due to incompatible package or library versions.
For more information about creating a new custom AMI, see the [Creating a custom AMI](#using-features.customenv.create) earlier in this topic.
### Removing a custom AMI
If you would like to remove a custom AMI from an environment and reset it to use the stock AMI for the environment’s platform version, use the following CLI command.
```
aws elasticbeanstalk update-environment \
--application-name my-application \
--environment-name my-environment \
--region us-east-1 \
--options-to-remove Namespace=aws:autoscaling:launchconfiguration,OptionName=ImageId
```
**Note**
To avoid disruption of your service, test your application with a stock AMI before applying this change to your production environment.
## Cleaning up a custom AMI
When you are done with a custom AMI and don't need it to launch Elastic Beanstalk environments anymore, consider cleaning it up to minimize storage cost. Cleaning up a custom AMI involves deregistering it from Amazon EC2 and deleting other associated resources. For details, see [Deregistering Your Linux AMI](https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/deregister-ami.html) or [Deregistering Your Windows AMI](https://docs.aws.amazon.com/AWSEC2/latest/WindowsGuide/deregister-ami.html).