Using cfn-init, ec2 instance keeps stopping when - amazon-web-services

Question

Trying to test cfn-init with an AWS Linux AMI. The instance is getting created but automatically stopping. Even if I try to manually start the instance, it immediately stops itself. Not sure what I'm doing wrong that the instance is stopping like that. All I'm doing is trying to test this out and setting up a file with cfn-init. This is taken from a template I found online. Any help's appreciated.
{
"AWSTemplateFormatVersion": "2010-09-09",
"Parameters": {
"VPC": {
"Type": "AWS::EC2::VPC::Id",
"Description": "Select the VPC where the EC2 instances will be created",
"ConstraintDescription": "must be an existing VPC"
},
"LinuxSubnet": {
"Type": "AWS::EC2::Subnet::Id",
"Description": "Select subnet for Linux Instance",
"ConstraintDescription": "must be an existing subnet"
},
"RemoteAccessCIDR": {
"Description": "CIDR block to allow access to linux instances",
"Type": "String",
"Default": "10.255.0.0/16",
"AllowedPattern": "(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})\\.(\\d{1,3})/(\\d{1,2})",
"ConstraintDescription": "must be a valid IP CIDR range of the form x.x.x.x/x."
},
"LinuxInstanceType": {
"Default": "t2.micro",
"Description": "Amazon EC2 Linux Instance Type",
"Type": "String"
},
"LinuxSecurityGroupIds": {
"Type": "String",
"Description": "Name of security group to use",
},
"LinuxSSHPort": {
"Description": "SSH Port Number on Linux client",
"Type": "Number",
"Default": 22,
"ConstraintDescription": "must be 22 or a number from 1024 to 65535"
},
"LinuxVolumeSize": {
"Description": "Size of EBS volume for Linux instance in GB",
"Type": "Number",
"Default": 8,
"ConstraintDescription": "must be 8 or higher"
},
"KeyPair": {
"Description": "Name of existing EC2 key pair for Linux Instances",
"Type": "AWS::EC2::KeyPair::KeyName"
}
},
"Resources": {
"TestMachine": {
"Type": "AWS::EC2::Instance",
"Metadata": {
"AWS::CloudFormation::Init": {
"configSets": {
"CreateStuff": "CreateFile"
},
"CreateFile" : {
"files": {
"/tmp/testing.txt": {
"content": "hopefully this works",
"mode": "0755",
"owner": "root",
"group": "root"
}
}
}
}
},
"Properties": {
"ImageId": "ami-0533f2ba8a1995cf9",
"InstanceType": {
"Ref": "LinuxInstanceType"
},
"SubnetId": {
"Ref": "LinuxSubnet"
},
"SecurityGroupIds": [{
"Ref": "LinuxSecurityGroupIds"
}],
"KeyName": {
"Ref": "KeyPair"
},
"Tags": [
{
"Key": "Automatic Patches",
"Value": "True"
},
{
"Key": "Description",
"Value": "Service-Catalog-EC2-Reference-Architecture"
},
{
"Key": "acr:CostCenter",
"Value": "986002"
},
{
"Key": "acr:Project",
"Value": "aws infrastructure general"
},
{
"Key": "Name",
"Value": "cfn-init-vm1"
}
],
"BlockDeviceMappings": [
{
"DeviceName": "/dev/sda1",
"Ebs": {
"Encrypted": "true",
"DeleteOnTermination":"true",
"VolumeSize": {
"Ref": "LinuxVolumeSize"
}
}
}
],
"UserData": {
"Fn::Base64" : { "Fn::Join" : ["", [
"#!/bin/bash -xe\n",
"yum install -y aws-cfn-bootstrap\n",
"# Install the files and packages from the metadata\n",
"/opt/aws/bin/cfn-init -v ",
" --stack ", { "Ref" : "AWS::StackName" },
" --resource TestMachine ",
" --configsets CreateStuff ",
" --region ", "us-east-1", "\n"
]]}
}
}
}
},
"Outputs": {
}
}