How to fix Error: Instance cannot be destroyed - resource has lifecycle.prevent_destroy set in Terraform

First, identify which resource has prevent_destroy enabled and confirm it's actually set to true.

# Look for this pattern in your Terraform configuration
resource "aws_instance" "example" {
  # ... configuration ...

  lifecycle {
    prevent_destroy = true
  }
}

If you see this in your code, this is the cause. Note the resource type and name for the next steps.

If you genuinely want to destroy this resource, set prevent_destroy to false or remove the lifecycle block entirely.

# Option 1: Change to false
resource "aws_instance" "example" {
  # ... configuration ...

  lifecycle {
    prevent_destroy = false
  }
}

# Option 2: Remove the lifecycle block entirely
resource "aws_instance" "example" {
  # ... configuration ...
}

After making this change, run terraform plan to verify the change is recognized:

terraform plan

Then you can proceed with destroy:

terraform apply  # Apply the plan that now allows destruction
terraform destroy  # Or destroy specific resource

If you want to unmanage the resource (stop Terraform from tracking it) without actually destroying it in your cloud provider, use terraform state rm:

terraform state rm aws_instance.example

This removes the resource from Terraform's state file, but the actual infrastructure remains running in AWS (or your provider). This is useful when:
- You want to manage the resource outside of Terraform
- You're migrating the resource to a different Terraform configuration
- You want to keep the resource but stop protecting it

Verify the resource was removed from state:

terraform state list | grep example

The resource should no longer appear in the state.

If the protected resource is in a nested module and you cannot edit the module directly, you have limited options:

1. Request the module owner/maintainer to add a variable to make prevent_destroy configurable:

variable "prevent_destroy" {
  type    = bool
  default = true
}

lifecycle {
  prevent_destroy = var.prevent_destroy
}

2. Fork/copy the module and customize it for your use case

3. Use terraform state rm to remove the module's resources from state before destroying the parent module:

terraform state rm 'module.my_module.aws_instance.example'

4. As a last resort, manually delete the infrastructure outside Terraform, then clean up state:

# Manually delete in cloud console, then
terraform state rm <resource_address>