# Use `CreateLaunchTemplate` with an AWS SDK or CLI
The following code examples show how to use `CreateLaunchTemplate`.
Action examples are code excerpts from larger programs and must be run in context. You can see this action in context in the following code examples:
+ [Build and manage a resilient service](example_cross_ResilientService_section.md)
+ [VPC with private servers](example_vpc_GettingStartedPrivate_section.md)
------
#### [ .NET ]
**SDK for .NET**
There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/dotnetv3/cross-service/ResilientService/AutoScalerActions#code-examples).
```
///
/// Creates an Amazon EC2 launch template to use with Amazon EC2 Auto Scaling.
/// The launch template specifies a Bash script in its user data field that runs after
/// the instance is started. This script installs the Python packages and starts a Python
/// web server on the instance.
///
/// The path to a Bash script file that is run.
/// The path to a permissions policy to create and attach to the profile.
/// The template object.
public async Task CreateTemplate(string startupScriptPath, string instancePolicyPath)
{
try
{
await CreateKeyPair(_keyPairName);
await CreateInstanceProfileWithName(_instancePolicyName, _instanceRoleName,
_instanceProfileName, instancePolicyPath);
var startServerText = await File.ReadAllTextAsync(startupScriptPath);
var plainTextBytes = System.Text.Encoding.UTF8.GetBytes(startServerText);
var amiLatest = await _amazonSsm.GetParameterAsync(
new GetParameterRequest() { Name = _amiParam });
var amiId = amiLatest.Parameter.Value;
var launchTemplateResponse = await _amazonEc2.CreateLaunchTemplateAsync(
new CreateLaunchTemplateRequest()
{
LaunchTemplateName = _launchTemplateName,
LaunchTemplateData = new RequestLaunchTemplateData()
{
InstanceType = _instanceType,
ImageId = amiId,
IamInstanceProfile =
new
LaunchTemplateIamInstanceProfileSpecificationRequest()
{
Name = _instanceProfileName
},
KeyName = _keyPairName,
UserData = System.Convert.ToBase64String(plainTextBytes)
}
});
return launchTemplateResponse.LaunchTemplate;
}
catch (AmazonEC2Exception ec2Exception)
{
if (ec2Exception.ErrorCode == "InvalidLaunchTemplateName.AlreadyExistsException")
{
_logger.LogError($"Could not create the template, the name {_launchTemplateName} already exists. " +
$"Please try again with a unique name.");
}
throw;
}
catch (Exception ex)
{
_logger.LogError($"An error occurred while creating the template.: {ex.Message}");
throw;
}
}
```
+ For API details, see [CreateLaunchTemplate](https://docs.aws.amazon.com/goto/DotNetSDKV3/ec2-2016-11-15/CreateLaunchTemplate) in *AWS SDK for .NET API Reference*.
------
#### [ CLI ]
**AWS CLI**
**Example 1: To create a launch template**
The following `create-launch-template` example creates a launch template that specifies the subnet in which to launch the instance , assigns a public IP address and an IPv6 address to the instance, and creates a tag for the instance.
```
aws ec2 create-launch-template \
--launch-template-name TemplateForWebServer \
--version-description WebVersion1 \
--launch-template-data '{"NetworkInterfaces":[{"AssociatePublicIpAddress":true,"DeviceIndex":0,"Ipv6AddressCount":1,"SubnetId":"subnet-7b16de0c"}],"ImageId":"ami-8c1be5f6","InstanceType":"t2.small","TagSpecifications":[{"ResourceType":"instance","Tags":[{"Key":"purpose","Value":"webserver"}]}]}'
```
Output:
```
{
"LaunchTemplate": {
"LatestVersionNumber": 1,
"LaunchTemplateId": "lt-01238c059e3466abc",
"LaunchTemplateName": "TemplateForWebServer",
"DefaultVersionNumber": 1,
"CreatedBy": "arn:aws:iam::123456789012:user/Bob",
"CreateTime": "2019-01-27T09:13:24.000Z"
}
}
```
For more information, see Launching an Instance from a Launch Template in the *Amazon Elastic Compute Cloud User Guide*. For information about quoting JSON-formatted parameters, see Quoting Strings in the *AWS Command Line Interface User Guide*.
**Example 2: To create a launch template for Amazon EC2 Auto Scaling**
The following `create-launch-template` example creates a launch template with multiple tags and a block device mapping to specify an additional EBS volume when an instance launches. Specify a value for `Groups` that corresponds to security groups for the VPC that your Auto Scaling group will launch instances into. Specify the VPC and subnets as properties of the Auto Scaling group.
```
aws ec2 create-launch-template \
--launch-template-name TemplateForAutoScaling \
--version-description AutoScalingVersion1 \
--launch-template-data '{"NetworkInterfaces":[{"DeviceIndex":0,"AssociatePublicIpAddress":true,"Groups":["sg-7c227019,sg-903004f8"],"DeleteOnTermination":true}],"ImageId":"ami-b42209de","InstanceType":"m4.large","TagSpecifications":[{"ResourceType":"instance","Tags":[{"Key":"environment","Value":"production"},{"Key":"purpose","Value":"webserver"}]},{"ResourceType":"volume","Tags":[{"Key":"environment","Value":"production"},{"Key":"cost-center","Value":"cc123"}]}],"BlockDeviceMappings":[{"DeviceName":"/dev/sda1","Ebs":{"VolumeSize":100}}]}' --region us-east-1
```
Output:
```
{
"LaunchTemplate": {
"LatestVersionNumber": 1,
"LaunchTemplateId": "lt-0123c79c33a54e0abc",
"LaunchTemplateName": "TemplateForAutoScaling",
"DefaultVersionNumber": 1,
"CreatedBy": "arn:aws:iam::123456789012:user/Bob",
"CreateTime": "2019-04-30T18:16:06.000Z"
}
}
```
For more information, see Creating a Launch Template for an Auto Scaling Group in the *Amazon EC2 Auto Scaling User Guide*. For information about quoting JSON-formatted parameters, see Quoting Strings in the *AWS Command Line Interface User Guide*.
**Example 3: To create a launch template that specifies encryption of EBS volumes**
The following `create-launch-template` example creates a launch template that includes encrypted EBS volumes created from an unencrypted snapshot. It also tags the volumes during creation. If encryption by default is disabled, you must specify the `"Encrypted"` option as shown in the following example. If you use the `"KmsKeyId"` option to specify a customer managed CMK, you also must specify the `"Encrypted"` option even if encryption by default is enabled.
```
aws ec2 create-launch-template \
--launch-template-name TemplateForEncryption \
--launch-template-data file://config.json
```
Contents of `config.json`:
```
{
"BlockDeviceMappings":[
{
"DeviceName":"/dev/sda1",
"Ebs":{
"VolumeType":"gp2",
"DeleteOnTermination":true,
"SnapshotId":"snap-066877671789bd71b",
"Encrypted":true,
"KmsKeyId":"arn:aws:kms:us-east-1:012345678910:key/abcd1234-a123-456a-a12b-a123b4cd56ef"
}
}
],
"ImageId":"ami-00068cd7555f543d5",
"InstanceType":"c5.large",
"TagSpecifications":[
{
"ResourceType":"volume",
"Tags":[
{
"Key":"encrypted",
"Value":"yes"
}
]
}
]
}
```
Output:
```
{
"LaunchTemplate": {
"LatestVersionNumber": 1,
"LaunchTemplateId": "lt-0d5bd51bcf8530abc",
"LaunchTemplateName": "TemplateForEncryption",
"DefaultVersionNumber": 1,
"CreatedBy": "arn:aws:iam::123456789012:user/Bob",
"CreateTime": "2020-01-07T19:08:36.000Z"
}
}
```
For more information, see Restoring an Amazon EBS Volume from a Snapshot and Encryption by Default in the *Amazon Elastic Compute Cloud User Guide*.
+ For API details, see [CreateLaunchTemplate](https://awscli.amazonaws.com/v2/documentation/api/latest/reference/ec2/create-launch-template.html) in *AWS CLI Command Reference*.
------
#### [ JavaScript ]
**SDK for JavaScript (v3)**
There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/javascriptv3/example_code/cross-services/wkflw-resilient-service#code-examples).
```
const ssmClient = new SSMClient({});
const { Parameter } = await ssmClient.send(
new GetParameterCommand({
Name: "/aws/service/ami-amazon-linux-latest/amzn2-ami-hvm-x86_64-gp2",
}),
);
const ec2Client = new EC2Client({});
await ec2Client.send(
new CreateLaunchTemplateCommand({
LaunchTemplateName: NAMES.launchTemplateName,
LaunchTemplateData: {
InstanceType: "t3.micro",
ImageId: Parameter.Value,
IamInstanceProfile: { Name: NAMES.instanceProfileName },
UserData: readFileSync(
join(RESOURCES_PATH, "server_startup_script.sh"),
).toString("base64"),
KeyName: NAMES.keyPairName,
},
}),
```
+ For API details, see [CreateLaunchTemplate](https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/client/ec2/command/CreateLaunchTemplateCommand) in *AWS SDK for JavaScript API Reference*.
------
#### [ Python ]
**SDK for Python (Boto3)**
There's more on GitHub. Find the complete example and learn how to set up and run in the [AWS Code Examples Repository](https://github.com/awsdocs/aws-doc-sdk-examples/tree/main/python/example_code/ec2#code-examples).
This example creates a launch template that includes an instance profile that grants specific permissions to the instance, and a user data Bash script that runs on the instance after it starts.
```
class AutoScalingWrapper:
"""
Encapsulates Amazon EC2 Auto Scaling and EC2 management actions.
"""
def __init__(
self,
resource_prefix: str,
inst_type: str,
ami_param: str,
autoscaling_client: boto3.client,
ec2_client: boto3.client,
ssm_client: boto3.client,
iam_client: boto3.client,
):
"""
Initializes the AutoScaler class with the necessary parameters.
:param resource_prefix: The prefix for naming AWS resources that are created by this class.
:param inst_type: The type of EC2 instance to create, such as t3.micro.
:param ami_param: The Systems Manager parameter used to look up the AMI that is created.
:param autoscaling_client: A Boto3 EC2 Auto Scaling client.
:param ec2_client: A Boto3 EC2 client.
:param ssm_client: A Boto3 Systems Manager client.
:param iam_client: A Boto3 IAM client.
"""
self.inst_type = inst_type
self.ami_param = ami_param
self.autoscaling_client = autoscaling_client
self.ec2_client = ec2_client
self.ssm_client = ssm_client
self.iam_client = iam_client
sts_client = boto3.client("sts")
self.account_id = sts_client.get_caller_identity()["Account"]
self.key_pair_name = f"{resource_prefix}-key-pair"
self.launch_template_name = f"{resource_prefix}-template-"
self.group_name = f"{resource_prefix}-group"
# Happy path
self.instance_policy_name = f"{resource_prefix}-pol"
self.instance_role_name = f"{resource_prefix}-role"
self.instance_profile_name = f"{resource_prefix}-prof"
# Failure mode
self.bad_creds_policy_name = f"{resource_prefix}-bc-pol"
self.bad_creds_role_name = f"{resource_prefix}-bc-role"
self.bad_creds_profile_name = f"{resource_prefix}-bc-prof"
def create_template(
self, server_startup_script_file: str, instance_policy_file: str
) -> Dict[str, Any]:
"""
Creates an Amazon EC2 launch template to use with Amazon EC2 Auto Scaling. The
launch template specifies a Bash script in its user data field that runs after
the instance is started. This script installs Python packages and starts a
Python web server on the instance.
:param server_startup_script_file: The path to a Bash script file that is run
when an instance starts.
:param instance_policy_file: The path to a file that defines a permissions policy
to create and attach to the instance profile.
:return: Information about the newly created template.
"""
template = {}
try:
# Create key pair and instance profile
self.create_key_pair(self.key_pair_name)
self.create_instance_profile(
instance_policy_file,
self.instance_policy_name,
self.instance_role_name,
self.instance_profile_name,
)
# Read the startup script
with open(server_startup_script_file) as file:
start_server_script = file.read()
# Get the latest AMI ID
ami_latest = self.ssm_client.get_parameter(Name=self.ami_param)
ami_id = ami_latest["Parameter"]["Value"]
# Create the launch template
lt_response = self.ec2_client.create_launch_template(
LaunchTemplateName=self.launch_template_name,
LaunchTemplateData={
"InstanceType": self.inst_type,
"ImageId": ami_id,
"IamInstanceProfile": {"Name": self.instance_profile_name},
"UserData": base64.b64encode(
start_server_script.encode(encoding="utf-8")
).decode(encoding="utf-8"),
"KeyName": self.key_pair_name,
},
)
template = lt_response["LaunchTemplate"]
log.info(
f"Created launch template {self.launch_template_name} for AMI {ami_id} on {self.inst_type}."
)
except ClientError as err:
log.error(f"Failed to create launch template {self.launch_template_name}.")
error_code = err.response["Error"]["Code"]
if error_code == "InvalidLaunchTemplateName.AlreadyExistsException":
log.info(
f"Launch template {self.launch_template_name} already exists, nothing to do."
)
log.error(f"Full error:\n\t{err}")
return template
```
+ For API details, see [CreateLaunchTemplate](https://docs.aws.amazon.com/goto/boto3/ec2-2016-11-15/CreateLaunchTemplate) in *AWS SDK for Python (Boto3) API Reference*.
------
For a complete list of AWS SDK developer guides and code examples, see [Create Amazon EC2 resources using an AWS SDK](sdk-general-information-section.md). This topic also includes information about getting started and details about previous SDK versions.