# Launch EC2 instances using a launch template An Amazon EC2 launch template stores instance launch parameters so that you don't have to specify them every time you launch an instance. Several instance launch services can optionally use launch templates when launching instances, while for other services, like EC2 Fleet, instances can't be launched unless a launch template is used. This topic describes how to use a launch template when launching an instance using the EC2 launch instance wizard, Amazon EC2 Auto Scaling, EC2 Fleet, and Spot Fleet. For more information about launch templates, including how to create a launch template, see [Store instance launch parameters in Amazon EC2 launch templates](ec2-launch-templates.md). **Topics** + [Launch an Amazon EC2 instance using a launch template](#launch-instance-from-launch-template) + [Launch instances in an Amazon EC2 Auto Scaling group using a launch template](#launch-templates-as) + [Launch an EC2 Fleet using a launch template](#launch-templates-ec2-fleet) + [Launch a Spot Fleet using a launch template](#launch-templates-spot-fleet) ## Launch an Amazon EC2 instance using a launch template You can use the parameters contained in a launch template to launch an Amazon EC2 instance. After selecting the launch template, but before launching the instance, you can modify the launch parameters. Instances that are launched using a launch template are automatically assigned two tags with the keys `aws:ec2launchtemplate:id` and `aws:ec2launchtemplate:version`. You can't remove or edit these tags. ------ #### [ Console ] **To launch an instance using a launch template** 1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/). 1. Use one of the following options to select the launch template: + From the Amazon EC2 console dashboard, choose the down arrow next to **Launch instance**, choose **Launch instance from template**, and then for **Source template**, select a launch template. + In the navigation pane, choose **Launch Templates**, select the launch template, and choose **Actions**, **Launch instance from template**. 1. For **Source template version**, select the launch template version to use. 1. (Optional) You can modify the values for any of the launch parameters. If you don't modify a value, the value defined by the launch template is used. If no value was specified in the launch template, the default value for the parameter is used. 1. In the **Summary** panel, for **Number of instances**, specify the number of instances to launch. 1. Choose **Launch instance**. If the instance fails to launch or the state immediately goes to `terminated` instead of `running`, see [Troubleshoot Amazon EC2 instance launch issues](troubleshooting-launch.md). ------ #### [ AWS CLI ] **To launch an instance from a launch template** + Use the [run-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/run-instances.html) command and specify the `--launch-template` parameter. Optionally specify the launch template version to use. If you don't specify the version, the default version is used. ``` aws ec2 run-instances \ --launch-template LaunchTemplateId=lt-0abcd290751193123,Version=1 ``` + To override a launch template parameter, specify the parameter in the [run-instances](https://docs.aws.amazon.com/cli/latest/reference/ec2/run-instances.html) command. The following example overrides the instance type that's specified in the launch template (if any). ``` aws ec2 run-instances \ --launch-template LaunchTemplateId=lt-0abcd290751193123 \ --instance-type t2.small ``` + If you specify a nested parameter that's part of a complex structure, the instance is launched using the complex structure as specified in the launch template plus any additional nested parameters that you specify. In the following example, the instance is launched with the tag `Owner=TeamA` as well as any other tags that are specified in the launch template. If the launch template has an existing tag with a key of `Owner`, the value is replaced with `TeamA`. ``` aws ec2 run-instances \ --launch-template LaunchTemplateId=lt-0abcd290751193123 \ --tag-specifications "ResourceType=instance,Tags=[{Key=Owner,Value=TeamA}]" ``` In the following example, the instance is launched with a volume with the device name *`/dev/xvdb`* as well as any other block device mappings that are specified in the launch template. If the launch template has an existing volume defined for *`/dev/xvdb`*, its values are replaced with the specified values. ``` aws ec2 run-instances \ --launch-template LaunchTemplateId=lt-0abcd290751193123 \ --block-device-mappings "DeviceName=/dev/xvdb,Ebs={VolumeSize=20,VolumeType=gp2}" ``` If the instance fails to launch or the state immediately goes to `terminated` instead of `running`, see [Troubleshoot Amazon EC2 instance launch issues](troubleshooting-launch.md). ------ #### [ PowerShell ] **To launch an instance from a launch template using the AWS Tools for PowerShell** + Use the [New-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/Index.html) command and specify the `-LaunchTemplate` parameter. Optionally specify the launch template version to use. If you don't specify the version, the default version is used. ``` Import-Module AWS.Tools.EC2 New-EC2Instance ` -LaunchTemplate ( New-Object -TypeName Amazon.EC2.Model.LaunchTemplateSpecification -Property @{ LaunchTemplateId = 'lt-0abcd290751193123'; Version = '4' } ) ``` + To override a launch template parameter, specify the parameter in the [New-EC2Instance](https://docs.aws.amazon.com/powershell/latest/reference/Index.html) command. The following example overrides the instance type that's specified in the launch template (if any). ``` Import-Module AWS.Tools.EC2 New-EC2Instance ` -InstanceType t4g.small ` -LaunchTemplate ( New-Object -TypeName Amazon.EC2.Model.LaunchTemplateSpecification -Property @{ LaunchTemplateId = 'lt-0abcd290751193123'; Version = '4' } ) ``` + If you specify a nested parameter that's part of a complex structure, the instance is launched using the complex structure as specified in the launch template plus any additional nested parameters that you specify. In the following example, the instance is launched with the tag `Owner=TeamA` as well as any other tags that are specified in the launch template. If the launch template has an existing tag with a key of `Owner`, the value is replaced with `TeamA`. ``` Import-Module AWS.Tools.EC2 New-EC2Instance ` -InstanceType t4g.small ` -LaunchTemplate ( New-Object -TypeName Amazon.EC2.Model.LaunchTemplateSpecification -Property @{ LaunchTemplateId = 'lt-0abcd290751193123'; Version = '4' } ) ` -TagSpecification ( New-Object -TypeName Amazon.EC2.Model.TagSpecification -Property @{ ResourceType = 'instance'; Tags = @( @{key = "Owner"; value = "TeamA" }, @{key = "Department"; value = "Operations" } ) } ) ``` In the following example, the instance is launched with a volume with the device name *`/dev/xvdb`* as well as any other block device mappings that are specified in the launch template. If the launch template has an existing volume defined for *`/dev/xvdb`*, its values are replaced with the specified values. ``` Import-Module AWS.Tools.EC2 New-EC2Instance ` -InstanceType t4g.small ` -LaunchTemplate ( New-Object -TypeName Amazon.EC2.Model.LaunchTemplateSpecification -Property @{ LaunchTemplateId = 'lt-0abcd290751193123'; Version = '4' } ) ` -BlockDeviceMapping ( New-Object -TypeName Amazon.EC2.Model.BlockDeviceMapping -Property @{ DeviceName = '/dev/xvdb'; EBS = ( New-Object -TypeName Amazon.EC2.Model.EbsBlockDevice -Property @{ VolumeSize = 25; VolumeType = 'gp3' } ) } ) ``` If the instance fails to launch or the state immediately goes to `terminated` instead of `running`, see [Troubleshoot Amazon EC2 instance launch issues](troubleshooting-launch.md). ------ ## Launch instances in an Amazon EC2 Auto Scaling group using a launch template You can create an Auto Scaling group and specify a launch template to use for the group. When Amazon EC2 Auto Scaling launches instances in the Auto Scaling group, it uses the launch parameters defined in the associated launch template. Before you can create an Auto Scaling group using a launch template, you must first create a launch template that includes the parameters required to launch an instance in an Auto Scaling group. Some parameters are required, such as the ID of the AMI, and some parameters are not available to use with an Auto Scaling group. The console provides guidance to help you create a template that you can use with Amazon EC2 Auto Scaling. **To create an Auto Scaling group with a launch template using the console** + For the instructions, see [Create an Auto Scaling group using a launch template]() in the *Amazon EC2 Auto Scaling User Guide*. **To create or update an Auto Scaling group with a launch template using the AWS CLI** + Use the [create-auto-scaling-group](https://docs.aws.amazon.com/cli/latest/reference/autoscaling/create-auto-scaling-group.html) or the [update-auto-scaling-group](https://docs.aws.amazon.com/cli/latest/reference/autoscaling/update-auto-scaling-group.html) command and specify the `--launch-template` parameter. For more information, see the following topics in the *Amazon EC2 Auto Scaling User Guide*: + [Create a launch template for an Auto Scaling group](https://docs.aws.amazon.com/autoscaling/ec2/userguide/create-launch-template.html) + [Create a launch template using advanced settings](https://docs.aws.amazon.com/autoscaling/ec2/userguide/advanced-settings-for-your-launch-template.html) + [Examples for creating and managing launch templates with the AWS Command Line Interface (AWS CLI)](https://docs.aws.amazon.com/autoscaling/ec2/userguide/examples-launch-templates-aws-cli.html) – Provides examples that show how to create launch templates with various parameter combinations. + [Create Auto Scaling groups using launch templates](https://docs.aws.amazon.com/autoscaling/ec2/userguide/create-auto-scaling-groups-launch-template.html) + [Update an Auto Scaling group](https://docs.aws.amazon.com/autoscaling/ec2/userguide/update-auto-scaling-group.html) ## Launch an EC2 Fleet using a launch template A launch template is a requirement when creating an EC2 Fleet request. When Amazon EC2 fulfills the EC2 Fleet request, it uses the launch parameters defined in the associated launch template. You can override some of the parameters that are specified in the launch template. For more information, see [Create an EC2 Fleet](create-ec2-fleet.md). **To create an EC2 Fleet with a launch template using the AWS CLI** + Use the [create-fleet](https://docs.aws.amazon.com/cli/latest/reference/ec2/create-fleet.html) command. Use the `--launch-template-configs` parameter to specify the launch template and any overrides for the launch template. ## Launch a Spot Fleet using a launch template A launch template is optional when creating a Spot Fleet request. If you don't use a launch template, you can manually specify the launch parameters. If you use a launch template, when Amazon EC2 fulfills the Spot Fleet request, it uses the launch parameters defined in the associated launch template. You can override some of the parameters that are specified in the launch template. For more information, see [Create a Spot Fleet](create-spot-fleet.md). **To create a Spot Fleet request using a launch template** 1. Open the Amazon EC2 console at [https://console.aws.amazon.com/ec2/](https://console.aws.amazon.com/ec2/). 1. In the navigation pane, choose **Spot Requests**. 1. Choose **Request Spot Instances**. 1. Under **Launch parameters**, choose **Use a launch template**. 1. For **Launch template**, choose a launch template, and then, from the field to the right, choose the launch template version. 1. Configure your Spot Fleet by selecting different options on this screen. For more information about the options, see [Create a Spot Fleet request using defined parameters](create-spot-fleet.md#create-spot-fleet-advanced). 1. When you're ready to create your Spot Fleet, choose **Launch**. **To create a Spot Fleet request using a launch template** + Use the [request-spot-fleet](https://docs.aws.amazon.com/cli/latest/reference/ec2/request-spot-fleet.html) command. Use the `LaunchTemplateConfigs` parameter to specify the launch template and any overrides for the launch template.