amazon-web-servicesamazon-ec2terraform
Why AWS aws_instance creates 2 instances instead of 1?
In my Terraform I create an Instance with an elastic ip:
data "aws_ami" "ubuntu" {
most_recent = true
filter {
name = "name"
values = ["ubuntu/images/hvm-ssd/ubuntu-jammy-22.04-amd64-server-*"]
}
filter {
name = "virtualization-type"
values = ["hvm"]
}
owners = ["099720109477"] # Canonical
}
resource "aws_instance" "myapp_staging" {
ami=data.aws_ami.ubuntu.id
instance_type="t3a.micro"
root_block_device {
volume_size = 30
volume_type = "gp3"
}
vpc_security_group_ids=[
"XXXXXXXX"
]
tags={
Name="myapp_staging"
}
volume_tags = {
Name="myapp_staging"
}
}
resource "aws_eip" "myapp_staging_ip" {
tags = {
Environment="Staging"
Client="Esupport"
Type="IP"
}
}
resource "aws_eip_association" "eip_assoc" {
instance_id = aws_instance.myapp_staging.id
allocation_id = aws_eip.myapp_staging_ip.id
}
But on EC-2 Console I see 2 AWS instances to be created instead of 1:
And I cannot understand why.
The Terraform plan creates another instance named this:
Terraform used the selected providers to generate the following execution plan. Resource actions are indicated with the following symbols:
+ create
Terraform will perform the following actions:
# aws_eip.myapp_staging_ip will be created
+ resource "aws_eip" "myapp_staging_ip" {
+ allocation_id = (known after apply)
+ association_id = (known after apply)
+ carrier_ip = (known after apply)
+ customer_owned_ip = (known after apply)
+ domain = (known after apply)
+ id = (known after apply)
+ instance = (known after apply)
+ network_border_group = (known after apply)
+ network_interface = (known after apply)
+ private_dns = (known after apply)
+ private_ip = (known after apply)
+ public_dns = (known after apply)
+ public_ip = (known after apply)
+ public_ipv4_pool = (known after apply)
+ tags = {
+ "Environment" = "Staging"
+ "Type" = "IP"
}
+ tags_all = {
+ "Environment" = "Staging"
+ "Type" = "IP"
}
+ vpc = (known after apply)
}
# aws_eip_association.eip_assoc will be created
+ resource "aws_eip_association" "eip_assoc" {
+ allocation_id = (known after apply)
+ id = (known after apply)
+ instance_id = (known after apply)
+ network_interface_id = (known after apply)
+ private_ip_address = (known after apply)
+ public_ip = (known after apply)
}
# aws_instance.myapp_staging will be created
+ resource "aws_instance" "myapp_staging" {
+ ami = "ami-0d940f23d527c3ab1"
+ arn = (known after apply)
+ associate_public_ip_address = (known after apply)
+ availability_zone = (known after apply)
+ cpu_core_count = (known after apply)
+ cpu_threads_per_core = (known after apply)
+ disable_api_stop = (known after apply)
+ disable_api_termination = (known after apply)
+ ebs_optimized = (known after apply)
+ get_password_data = false
+ host_id = (known after apply)
+ host_resource_group_arn = (known after apply)
+ iam_instance_profile = (known after apply)
+ id = (known after apply)
+ instance_initiated_shutdown_behavior = (known after apply)
+ instance_state = (known after apply)
+ instance_type = "t3a.micro"
+ ipv6_address_count = (known after apply)
+ ipv6_addresses = (known after apply)
+ key_name = (known after apply)
+ monitoring = (known after apply)
+ outpost_arn = (known after apply)
+ password_data = (known after apply)
+ placement_group = (known after apply)
+ placement_partition_number = (known after apply)
+ primary_network_interface_id = (known after apply)
+ private_dns = (known after apply)
+ private_ip = (known after apply)
+ public_dns = (known after apply)
+ public_ip = (known after apply)
+ secondary_private_ips = (known after apply)
+ security_groups = (known after apply)
+ source_dest_check = true
+ subnet_id = (known after apply)
+ tags = {
+ "Name" = "myapp_staging"
}
+ tags_all = {
+ "Name" = "myapp_staging"
}
+ tenancy = (known after apply)
+ user_data = (known after apply)
+ user_data_base64 = (known after apply)
+ user_data_replace_on_change = false
+ volume_tags = {
+ "Name" = "myapp_staging"
}
+ vpc_security_group_ids = [
+ "XXXXXXXXX",
]
+ root_block_device {
+ delete_on_termination = true
+ device_name = (known after apply)
+ encrypted = (known after apply)
+ iops = (known after apply)
+ kms_key_id = (known after apply)
+ throughput = (known after apply)
+ volume_id = (known after apply)
+ volume_size = 30
+ volume_type = "gp3"
}
}
# module.ec2-instance.aws_instance.this[0] will be created
+ resource "aws_instance" "this" {
+ ami = "ami-0785f49d3c3be2037"
+ arn = (known after apply)
+ associate_public_ip_address = (known after apply)
+ availability_zone = (known after apply)
+ cpu_core_count = (known after apply)
+ cpu_threads_per_core = (known after apply)
+ disable_api_stop = (known after apply)
+ disable_api_termination = (known after apply)
+ ebs_optimized = (known after apply)
+ get_password_data = false
+ host_id = (known after apply)
+ host_resource_group_arn = (known after apply)
+ iam_instance_profile = (known after apply)
+ id = (known after apply)
+ instance_initiated_shutdown_behavior = (known after apply)
+ instance_state = (known after apply)
+ instance_type = "t3.micro"
+ ipv6_address_count = (known after apply)
+ ipv6_addresses = (known after apply)
+ key_name = (known after apply)
+ monitoring = (known after apply)
+ outpost_arn = (known after apply)
+ password_data = (known after apply)
+ placement_group = (known after apply)
+ placement_partition_number = (known after apply)
+ primary_network_interface_id = (known after apply)
+ private_dns = (known after apply)
+ private_ip = (known after apply)
+ public_dns = (known after apply)
+ public_ip = (known after apply)
+ secondary_private_ips = (known after apply)
+ security_groups = (known after apply)
+ source_dest_check = true
+ subnet_id = (known after apply)
+ tags = {
+ "Name" = ""
}
+ tags_all = {
+ "Name" = (known after apply)
}
+ tenancy = (known after apply)
+ user_data = (known after apply)
+ user_data_base64 = (known after apply)
+ user_data_replace_on_change = false
+ volume_tags = {
+ "Name" = ""
}
+ vpc_security_group_ids = (known after apply)
+ credit_specification {}
+ enclave_options {
+ enabled = (known after apply)
}
+ metadata_options {
+ http_endpoint = "enabled"
+ http_put_response_hop_limit = 1
+ http_tokens = "optional"
+ instance_metadata_tags = (known after apply)
}
+ timeouts {}
}
Plan: 4 to add, 0 to change, 0 to destroy.
What can I try next?
Solution
You have an aws_instance resource in your Terraform code, that is creating one EC2 instance. You are also using a Terraform module, named ec2-instance which you failed to include in your question, but can be seen in the Terraform plan output, that is also creating one EC2 instance.