How re-attache ebs volume using terraform - linux

Question

I'm trying to keep AWS EBS volume as a persistent data-store, every week my AMI changes so I have to spin-up new VM in aws. At this time I'm expecting my volume to detach from the old VM and attach to a new VM without destroying the EBS volume and data.
resource "aws_instance" "my_instance" {
count = var.instance_count
ami = lookup(var.ami,var.aws_region)
instance_type = var.instance_type
key_name = aws_key_pair.terraform-demo.key_name
subnet_id = aws_subnet.main-public-1.id
// user_data = "${file("install_apache.sh")}"
tags = {
Name = "Terraform-${count.index + 1}"
Batch = "5AM"
}
}
variable "instances" {
type = map
default = {
"xx" = "sss-console"
"4xx" = "sss-upload-port"
"xxx" = "sss"
}
}
resource "aws_kms_key" "cmp_kms" {
description = "ssss-ebsencrypt"
tags = local.all_labels
}
resource "aws_ebs_volume" "volumes" {
count = var.instance_count
availability_zone = element(aws_instance.my_instance.*.availability_zone, count.index )
encrypted = true
kms_key_id = aws_kms_key.cmp_kms.arn
size = local.volume_size
type = local.volume_type
iops = local.volume_iops
// tags = merge(var.extra_labels, map("Name", "${var.cell}-${element(local.volume_name, count.index)}"))
lifecycle {
// prevent_destroy = true
ignore_changes = [kms_key_id, instance_id]
}
}
resource "aws_volume_attachment" "volumes-attachment" {
depends_on = [aws_instance.my_instance, aws_ebs_volume.volumes]
count = var.instance_count
device_name = "/dev/${element(local.volume_name, count.index)}"
volume_id = element(aws_ebs_volume.volumes.*.id, count.index)
instance_id = element(aws_instance.my_instance.*.id, count.index)
force_detach = true
}
ERROR on terraform apply
Error: Unsupported attribute
on instance.tf line 71, in resource "aws_ebs_volume" "volumes":
71: ignore_changes = [kms_key_id, instance_id]
This object has no argument, nested block, or exported attribute named
"instance_id".
earlier the same code use to work with terraform v0.11 but it's not working with v0.12. what is the replacement for this or how can we re-attach EBS to a different machine without destroying it?

Answer 1

As per terraform documentation, they do not expose any attribute named as instance_id for resource aws_ebs_volume.
For reference: https://www.terraform.io/docs/providers/aws/d/ebs_volume.html.
You can specify the instance_id at the time of volume attachment using resource
aws_volume_attachment.
You can refer the answer given in https://gitter.im/hashicorp-terraform/Lobby?at=5ab900eb2b9dfdbc3a237e36 for more information.