Hi Techies,
We are going to see how to resolve ‘A managed resource “aws_subnet” “pubsubnet” has not been declared in the root module.’ error while using terraform to create 2 EC2 instance with VPC in AWS
code:
resource "aws_instance" "pub_instance" {
ami = "ami-033fabdd332044f06"
instance_type = "t2.micro"
availability_zone = "us-east-2a"
associate_public_ip_address = "true"
vpc_security_group_ids = [aws_security_group.PUBSG.id]
subnet_id = aws_subnet.pubsubnet.id
key_name = "Terraform_Srv"
tags = {
Name = "WEBSERVER"
}
}
resource "aws_instance" "pvt_instance" {
ami = "ami-033fabdd332044f06"
instance_type = "t2.micro"
availability_zone = "us-east-2b"
associate_public_ip_address = "true"
vpc_security_group_ids = [aws_security_group.PVTSG.id]
subnet_id = aws_subnet.pvtsubnet.id
key_name = "Terraform_Srv"
tags = {
Name = "APPSERVER"
}
Error:
[root@ip-172-31-7-226 terraform]# terraform apply ╷ │ Error: Reference to undeclared resource │ │ on main.tf line 163, in resource "aws_instance" "pub_instance": │ 163: subnet_id = aws_subnet.pubsubnet.id │ │ A managed resource "aws_subnet" "pubsubnet" has not been declared in the root module. ╵ ╷ │ Error: Reference to undeclared resource │ │ on main.tf line 178, in resource "aws_instance" "pvt_instance": │ 178: subnet_id = aws_subnet.pvtsubnet.id │ │ A managed resource "aws_subnet" "pvtsubnet" has not been declared in the root module.
After checking the full code of script, found that I have declared the names like PUBSUB & PVTSUB for public and private subnet wiseversa.
But I wrongly mentioned like pubsubnet & pvtsubnet in the EC2 instance creation. So, after renaming it to correctly like below it is fixed.
subnet_id = aws_subnet.pubsubnet.id subnet_id = aws_subnet.pubsubnet.id modified like below based on the declared name inn previous code subnet_id = aws_subnet.PUBSUB.id subnet_id = aws_subnet.PVTSUB.id
Result:
After changing the error was fixed and find the below result
aws_instance.pvt_instance: Creating... aws_instance.pub_instance: Creating... aws_route_table.PVTRT: Modifying... [id=rtb-05ab30d4598210e59] aws_route_table.PVTRT: Modifications complete after 0s [id=rtb-05ab30d4598210e59] aws_instance.pub_instance: Still creating... [10s elapsed] aws_instance.pvt_instance: Still creating... [10s elapsed] aws_instance.pvt_instance: Still creating... [20s elapsed] aws_instance.pub_instance: Still creating... [20s elapsed] aws_instance.pub_instance: Still creating... [30s elapsed] aws_instance.pvt_instance: Still creating... [30s elapsed] aws_instance.pvt_instance: Creation complete after 31s [id=i-096c28fbbaeff8a42] aws_instance.pub_instance: Creation complete after 31s [id=i-0f745c3aeca6327aa] Apply complete! Resources: 2 added, 1 changed, 0 destroyed. [root@ip-172-31-7-226 terraform]#