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Create a simple ec2 instance in VPC/Subnet of your choice, with SSM enabled so you can get a shell on it without opening SSH. This can be used to test connectivity between AWS locations. It runs a simple user_data.sh script that will install some common tools (docker) and login to the ECR registry of the AWS account.

The only required variables are the vpc_id and subnet_id where you want to creat the instance.

The instance MUST have access to AWS Apis for SSM to work. This can be via a IGW (public IP on instance, or via VPC-Endpoints, see Starting a service in an air gapped private Subnet)

Connecting to a created Server

You can get the instance id from Terraform and pass it straight into AWS CLI. Note the --raw which removes the quotes from the instance_id as AWS CLI fails if they are present.

aws ssm start-session --target $(terraform output --raw instance_id)

Starting a service in an air gapped private Subnet

SSM requires access to AWS APIs in order to work. This requires the server being placed in a Subnet that has outbound internet access. This can be either a public subnet using an Internet Gateway and public IP assigned to the instance, a private subnet with a NAT-Gateway, or in a subnet that has VPC Endpoints configured for ssmmessages, ssm, and ec2messages

Terraform Docs

In order to populate the following Terraform documentation, run the terraform-docs . command. The .terraform-docs.yml file contains the configuration to make sure if gets created in the correct way.

Requirements

Name Version
aws ~> 4.0

Providers

Name Version
aws ~> 4.0
random n/a
template n/a

Modules

No modules.

Resources

Name Type
aws_iam_instance_profile.profile resource
aws_iam_role.role resource
aws_instance.instance resource
aws_security_group.security_group resource
random_string.module_suffix resource
aws_ami.this data source
aws_caller_identity.current data source
aws_iam_policy_document.assume_policy data source
aws_region.current data source
template_file.user_data data source

Inputs

Name Description Type Default Required
additional_role_policies Additional Policies to attach to the instance in additional to SSM list(string) [] no
additional_security_groups Addition security groups to assign to the instance list(string) [] no
additional_tags Map of tags to add to all resources map(string) {} no
additional_user_data Additional code to be added to the user_data.sh script string null no
ami Specify an AMI to run, if not it will use the latest Amazon Linux, or Windows Server image. string "" no
associate_public_ip_address Assign public IP to the instance. bool true no
comment Comment tag to add to all resources string "" no
instance_name_override Override the name tag provided to the instance. default: -tmp-instance- string null no
instance_type AWS instance type to create string "t3.nano" no
key_name SSH key pair to use string "" no
subnet_id Subnet to create the instance in string n/a yes
volume_size Root volume size of instance number 10 no
vpc_id VPC to create the test instance in string n/a yes
windows Do you want to run a Windows server?... whyyy? bool false no

Outputs

Name Description
ami ID of the AMI that has been selected.
instance The created instance, allowing use of any of the attributes of the aws_instance resourfce
instance_id ID of the instance that has been created. Can be used in SSM Start session command with $(terraform output instance_id|jq -r)
instance_role The IAM role assigned to the instance
security_group The security group created for instance. Can be used to add additional rules