Terraform Module for provisioning a general purpose EC2 host.

Included features:

• Automatically create a Security Group
• Option to switch EIP attachment
• CloudWatch monitoring and automatic reboot if instance hangs
• Assume Role capability

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Usage

Note: add ${var.ssh_key_pair} private key to the ssh agent.

Include this repository as a module in your existing terraform code.

Simple example:

module "instance" {
  source = "cloudposse/ec2-instance/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  ssh_key_pair                = var.ssh_key_pair
  instance_type               = var.instance_type
  vpc_id                      = var.vpc_id
  security_groups             = var.security_groups
  subnet                      = var.subnet
  name                        = "ec2"
  namespace                   = "eg"
  stage                       = "dev"
}

Example with additional volumes and EIP

module "kafka_instance" {
  source = "cloudposse/ec2-instance/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  ssh_key_pair                = var.ssh_key_pair
  vpc_id                      = var.vpc_id
  security_groups             = var.security_groups
  subnet                      = var.subnet
  associate_public_ip_address = true
  name                        = "kafka"
  namespace                   = "eg"
  stage                       = "dev"
  additional_ips_count        = 1
  ebs_volume_count            = 2
  security_group_rules = [
    {
      type        = "egress"
      from_port   = 0
      to_port     = 65535
      protocol    = "-1"
      cidr_blocks = ["0.0.0.0/0"]
    },
    {
      type        = "ingress"
      from_port   = 22
      to_port     = 22
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
    },
    {
      type        = "ingress"
      from_port   = 80
      to_port     = 80
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
    },
    {
      type        = "ingress"
      from_port   = 443
      to_port     = 443
      protocol    = "tcp"
      cidr_blocks = ["0.0.0.0/0"]
    },
    {
      type        = "ingress"
      from_port   = 53
      to_port     = 53
      protocol    = "udp"
      cidr_blocks = ["0.0.0.0/0"]
    },
  ]
}

Important

In Cloud Posse's examples, we avoid pinning modules to specific versions to prevent discrepancies between the documentation and the latest released versions. However, for your own projects, we strongly advise pinning each module to the exact version you're using. This practice ensures the stability of your infrastructure. Additionally, we recommend implementing a systematic approach for updating versions to avoid unexpected changes.

Makefile Targets

Available targets:

  help                                Help screen
  help/all                            Display help for all targets
  help/short                          This help short screen
  lint                                Lint terraform code

Requirements

Name	Version
terraform	>= 1.0
aws	>= 4.7.0
null	>= 2.0

Providers

Name	Version
aws	>= 4.7.0
null	>= 2.0

Modules

Name	Source	Version
label_ssm_patch_s3_log_policy	cloudposse/label/null	0.25.0
security_group	cloudposse/security-group/aws	0.3.3
this	cloudposse/label/null	0.25.0

Resources

Name	Type
aws_cloudwatch_metric_alarm.default	resource
aws_ebs_volume.default	resource
aws_eip.additional	resource
aws_eip.default	resource
aws_iam_instance_profile.default	resource
aws_iam_policy.ssm_patch_s3_log_policy	resource
aws_iam_role.default	resource
aws_iam_role_policy_attachment.ssm_core	resource
aws_iam_role_policy_attachment.ssm_s3_policy	resource
aws_instance.default	resource
aws_network_interface.additional	resource
aws_network_interface_attachment.additional	resource
aws_volume_attachment.default	resource
null_resource.check_alarm_action	resource
aws_ami.default	data source
aws_ami.info	data source
aws_caller_identity.default	data source
aws_iam_instance_profile.given	data source
aws_iam_policy_document.default	data source
aws_iam_policy_document.ssm_patch_s3_log_policy	data source
aws_partition.default	data source
aws_region.default	data source
aws_subnet.default	data source

Inputs

Name	Description	Type	Default	Required
additional_ips_count	Count of additional EIPs	number	0	no
additional_tag_map	Additional key-value pairs to add to each map in tags_as_list_of_maps. Not added to tags or id. This is for some rare cases where resources want additional configuration of tags and therefore take a list of maps with tag key, value, and additional configuration.	map(string)	{}	no
ami	The AMI to use for the instance. By default it is the AMI provided by Amazon with Ubuntu 16.04	string	""	no
ami_owner	Owner of the given AMI (ignored if ami unset, required if set)	string	""	no
applying_period	The period in seconds over which the specified statistic is applied	number	60	no
assign_eip_address	Assign an Elastic IP address to the instance	bool	true	no
associate_public_ip_address	Associate a public IP address with the instance	bool	false	no
attributes	ID element. Additional attributes (e.g. workers or cluster) to add to id, in the order they appear in the list. New attributes are appended to the end of the list. The elements of the list are joined by the delimiter and treated as a single ID element.	list(string)	[]	no
availability_zone	Availability Zone the instance is launched in. If not set, will be launched in the first AZ of the region	string	""	no
burstable_mode	Enable burstable mode for the instance. Can be standard or unlimited. Applicable only for T2/T3/T4g instance types.	string	null	no
comparison_operator	The arithmetic operation to use when comparing the specified Statistic and Threshold. Possible values are: GreaterThanOrEqualToThreshold, GreaterThanThreshold, LessThanThreshold, LessThanOrEqualToThreshold.	string	"GreaterThanOrEqualToThreshold"	no
context	Single object for setting entire context at once. See description of individual variables for details. Leave string and numeric variables as null to use default value. Individual variable settings (non-null) override settings in context object, except for attributes, tags, and additional_tag_map, which are merged.	any	{ "additional_tag_map": {}, "attributes": [], "delimiter": null, "descriptor_formats": {}, "enabled": true, "environment": null, "id_length_limit": null, "label_key_case": null, "label_order": [], "label_value_case": null, "labels_as_tags": [ "unset" ], "name": null, "namespace": null, "regex_replace_chars": null, "stage": null, "tags": {}, "tenant": null }	no
default_alarm_action	Default alarm action	string	"action/actions/AWS_EC2.InstanceId.Reboot/1.0"	no
delete_on_termination	Whether the volume should be destroyed on instance termination	bool	true	no
delimiter	Delimiter to be used between ID elements. Defaults to - (hyphen). Set to "" to use no delimiter at all.	string	null	no
descriptor_formats	Describe additional descriptors to be output in the descriptors output map. Map of maps. Keys are names of descriptors. Values are maps of the form {<br/> format = string<br/> labels = list(string)<br/>} (Type is any so the map values can later be enhanced to provide additional options.) format is a Terraform format string to be passed to the format() function. labels is a list of labels, in order, to pass to format() function. Label values will be normalized before being passed to format() so they will be identical to how they appear in id. Default is {} (descriptors output will be empty).	any	{}	no
disable_alarm_action	Disable the creation of Alarm Action	bool	false	no
disable_api_stop	Enable EC2 Instance Stop Protection	bool	false	no
disable_api_termination	Enable EC2 Instance Termination Protection	bool	false	no
ebs_device_name	Name of the EBS device to mount	list(string)	[ "/dev/xvdb", "/dev/xvdc", "/dev/xvdd", "/dev/xvde", "/dev/xvdf", "/dev/xvdg", "/dev/xvdh", "/dev/xvdi", "/dev/xvdj", "/dev/xvdk", "/dev/xvdl", "/dev/xvdm", "/dev/xvdn", "/dev/xvdo", "/dev/xvdp", "/dev/xvdq", "/dev/xvdr", "/dev/xvds", "/dev/xvdt", "/dev/xvdu", "/dev/xvdv", "/dev/xvdw", "/dev/xvdx", "/dev/xvdy", "/dev/xvdz" ]	no
ebs_iops	Amount of provisioned IOPS. This must be set with a volume_type of io1, io2 or gp3	number	0	no
ebs_optimized	Launched EC2 instance will be EBS-optimized	bool	true	no
ebs_throughput	Amount of throughput. This must be set if volume_type is set to gp3	number	0	no
ebs_volume_count	Count of EBS volumes that will be attached to the instance	number	0	no
ebs_volume_encrypted	Whether to encrypt the additional EBS volumes	bool	true	no
ebs_volume_size	Size of the additional EBS volumes in gigabytes	number	10	no
ebs_volume_type	The type of the additional EBS volumes. Can be standard, gp2, gp3, io1 or io2	string	"gp2"	no
enabled	Set to false to prevent the module from creating any resources	bool	null	no
environment	ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'	string	null	no
evaluation_periods	The number of periods over which data is compared to the specified threshold.	number	5	no
external_network_interface_enabled	Wheter to attach an external ENI as the eth0 interface for the instance. Any change to the interface will force instance recreation.	bool	false	no
external_network_interfaces	The external interface definitions to attach to the instances. This depends on the instance type	list(object({ delete_on_termination = bool device_index = number network_card_index = number network_interface_id = string }))	null	no
force_detach_ebs	force the volume/s to detach from the instance.	bool	false	no
id_length_limit	Limit id to this many characters (minimum 6). Set to 0 for unlimited length. Set to null for keep the existing setting, which defaults to 0. Does not affect id_full.	number	null	no
instance_initiated_shutdown_behavior	Specifies whether an instance stops or terminates when you initiate shutdown from the instance. Can be one of 'stop' or 'terminate'.	string	null	no
instance_profile	A pre-defined profile to attach to the instance (default is to build our own)	string	""	no
instance_profile_enabled	Whether an IAM instance profile is created to pass a role to an Amazon EC2 instance when the instance starts	bool	true	no
instance_type	The type of the instance	string	"t2.micro"	no
ipv6_address_count	Number of IPv6 addresses to associate with the primary network interface. Amazon EC2 chooses the IPv6 addresses from the range of your subnet (-1 to use subnet default)	number	0	no
ipv6_addresses	List of IPv6 addresses from the range of the subnet to associate with the primary network interface	list(string)	[]	no
kms_key_id	KMS key ID used to encrypt EBS volume. When specifying kms_key_id, ebs_volume_encrypted needs to be set to true	string	null	no
label_key_case	Controls the letter case of the tags keys (label names) for tags generated by this module. Does not affect keys of tags passed in via the tags input. Possible values: lower, title, upper. Default value: title.	string	null	no
label_order	The order in which the labels (ID elements) appear in the id. Defaults to ["namespace", "environment", "stage", "name", "attributes"]. You can omit any of the 6 labels ("tenant" is the 6th), but at least one must be present.	list(string)	null	no
label_value_case	Controls the letter case of ID elements (labels) as included in id, set as tag values, and output by this module individually. Does not affect values of tags passed in via the tags input. Possible values: lower, title, upper and none (no transformation). Set this to title and set delimiter to "" to yield Pascal Case IDs. Default value: lower.	string	null	no
labels_as_tags	Set of labels (ID elements) to include as tags in the tags output. Default is to include all labels. Tags with empty values will not be included in the tags output. Set to [] to suppress all generated tags. Notes: The value of the name tag, if included, will be the id, not the name. Unlike other null-label inputs, the initial setting of labels_as_tags cannot be changed in later chained modules. Attempts to change it will be silently ignored.	set(string)	[ "default" ]	no
metadata_http_endpoint_enabled	Whether the metadata service is available	bool	true	no
metadata_http_put_response_hop_limit	The desired HTTP PUT response hop limit (between 1 and 64) for instance metadata requests.	number	2	no
metadata_http_tokens_required	Whether or not the metadata service requires session tokens, also referred to as Instance Metadata Service Version 2.	bool	true	no
metadata_tags_enabled	Whether the tags are enabled in the metadata service.	bool	false	no
metric_name	The name for the alarm's associated metric. Allowed values can be found in https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/ec2-metricscollected.html	string	"StatusCheckFailed_Instance"	no
metric_namespace	The namespace for the alarm's associated metric. Allowed values can be found in https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/aws-namespaces.html	string	"AWS/EC2"	no
metric_threshold	The value against which the specified statistic is compared	number	1	no
metric_treat_missing_data	Sets how this alarm is to handle missing data points. The following values are supported: missing, ignore, breaching and notBreaching. Defaults to missing.	string	"missing"	no
monitoring	Launched EC2 instance will have detailed monitoring enabled	bool	true	no
name	ID element. Usually the component or solution name, e.g. 'app' or 'jenkins'. This is the only ID element not also included as a tag. The "name" tag is set to the full id string. There is no tag with the value of the name input.	string	null	no
namespace	ID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique	string	null	no
permissions_boundary_arn	Policy ARN to attach to instance role as a permissions boundary	string	""	no
private_ip	Private IP address to associate with the instance in the VPC	string	null	no
regex_replace_chars	Terraform regular expression (regex) string. Characters matching the regex will be removed from the ID elements. If not set, "/[^a-zA-Z0-9-]/" is used to remove all characters other than hyphens, letters and digits.	string	null	no
region	AWS Region the instance is launched in	string	""	no
root_block_device_encrypted	Whether to encrypt the root block device	bool	true	no
root_block_device_kms_key_id	KMS key ID used to encrypt EBS volume. When specifying root_block_device_kms_key_id, root_block_device_encrypted needs to be set to true	string	null	no
root_iops	Amount of provisioned IOPS. This must be set if root_volume_type is set of io1, io2 or gp3	number	0	no
root_throughput	Amount of throughput. This must be set if root_volume_type is set to gp3	number	0	no
root_volume_size	Size of the root volume in gigabytes	number	10	no
root_volume_type	Type of root volume. Can be standard, gp2, gp3, io1 or io2	string	"gp2"	no
secondary_private_ips	List of secondary private IP addresses to associate with the instance in the VPC	list(string)	[]	no
security_group_description	The Security Group description.	string	"EC2 Security Group"	no
security_group_enabled	Whether to create default Security Group for EC2.	bool	true	no
security_group_rules	A list of maps of Security Group rules. The values of map is fully complated with aws_security_group_rule resource. To get more info see https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/security_group_rule .	list(any)	[ { "cidr_blocks": [ "0.0.0.0/0" ], "description": "Allow all outbound traffic", "from_port": 0, "protocol": "-1", "to_port": 65535, "type": "egress" } ]	no
security_group_use_name_prefix	Whether to create a default Security Group with unique name beginning with the normalized prefix.	bool	false	no
security_groups	A list of Security Group IDs to associate with EC2 instance.	list(string)	[]	no
source_dest_check	Controls if traffic is routed to the instance when the destination address does not match the instance. Used for NAT or VPNs	bool	true	no
ssh_key_pair	SSH key pair to be provisioned on the instance	string	null	no
ssm_patch_manager_enabled	Whether to enable SSM Patch manager	bool	false	no
ssm_patch_manager_iam_policy_arn	IAM policy ARN to allow Patch Manager to manage the instance. If not provided, arn:aws:iam::aws:policy/AmazonSSMManagedInstanceCore will be used	string	null	no
ssm_patch_manager_s3_log_bucket	The name of the s3 bucket to export the patch log to	string	null	no
stage	ID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'	string	null	no
statistic_level	The statistic to apply to the alarm's associated metric. Allowed values are: SampleCount, Average, Sum, Minimum, Maximum	string	"Maximum"	no
stop_ec2_before_detaching_vol	Set this to true to ensure that the target instance is stopped before trying to detach the volume/s.	bool	false	no
subnet	VPC Subnet ID the instance is launched in	string	n/a	yes
tags	Additional tags (e.g. {'BusinessUnit': 'XYZ'}). Neither the tag keys nor the tag values will be modified by this module.	map(string)	{}	no
tenancy	Tenancy of the instance (if the instance is running in a VPC). An instance with a tenancy of 'dedicated' runs on single-tenant hardware. The 'host' tenancy is not supported for the import-instance command. Valid values are 'default', 'dedicated', and 'host'.	string	"default"	no
tenant	ID element _(Rarely used, not included by default)_. A customer identifier, indicating who this instance of a resource is for	string	null	no
user_data	The user data to provide when launching the instance. Do not pass gzip-compressed data via this argument; use user_data_base64 instead	string	null	no
user_data_base64	Can be used instead of user_data to pass base64-encoded binary data directly. Use this instead of user_data whenever the value is not a valid UTF-8 string. For example, gzip-encoded user data must be base64-encoded and passed via this argument to avoid corruption	string	null	no
user_data_replace_on_change	When used in combination with user_data or user_data_base64 will trigger a destroy and recreate when set to true.	bool	false	no
volume_tags_enabled	Whether or not to copy instance tags to root and EBS volumes	bool	true	no
vpc_id	The ID of the VPC that the instance security group belongs to	string	n/a	yes

Outputs

Name	Description
additional_eni_ids	Map of ENI to EIP
alarm	CloudWatch Alarm ID
arn	ARN of the instance
ebs_ids	IDs of EBSs
id	Disambiguated ID of the instance
instance_profile	Name of the instance's profile (either built or supplied)
name	Instance name
primary_network_interface_id	ID of the instance's primary network interface
private_dns	Private DNS of instance
private_ip	Private IP of instance
public_dns	Public DNS of instance (or DNS of EIP)
public_ip	Public IP of instance (or EIP)
role	Name of AWS IAM Role associated with the instance
role_arn	ARN of AWS IAM Role associated with the instance
security_group_arn	EC2 instance Security Group ARN
security_group_id	EC2 instance Security Group ID
security_group_ids	IDs on the AWS Security Groups associated with the instance
security_group_name	EC2 instance Security Group name
ssh_key_pair	Name of the SSH key pair provisioned on the instance

Related Projects

Check out these related projects.

• terraform-aws-ec2-ami-backup - Terraform module for automatic & scheduled AMI creation
• terraform-aws-ec2-ami-snapshot - Terraform module to easily generate AMI snapshots to create replica instances
• terraform-aws-ec2-cloudwatch-sns-alarms - Terraform module that configures CloudWatch SNS alerts for EC2 instances
• terraform-null-label - Terraform Module to define a consistent naming convention by (namespace, stage, name, [attributes])

References

For additional context, refer to some of these links.

• terraform-aws-ec2-bastion-server - Terraform Module to define a generic Bastion host with parameterized user_data

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