Terraform's lifecycle meta-argument only accepts valid arguments like create_before_destroy, prevent_destroy, ignore_changes, precondition, and postcondition. This error occurs when you use an unsupported argument name or incorrect syntax in the lifecycle block.
This error indicates that Terraform encountered an unrecognized argument within a lifecycle block. The lifecycle meta-argument is a special block used to customize how Terraform manages the lifecycle of resources (creation, updates, and destruction), but it only accepts a specific set of valid arguments. When Terraform parses your configuration and finds an argument in the lifecycle block that it doesn't recognize, it raises this validation error and prevents the configuration from being applied. This is typically caused by: - Typos in argument names - Using outdated or incorrect argument syntax - Attempting to use dynamic blocks or variables in the lifecycle block (not supported) - Using provider-specific lifecycle_policy arguments instead of the lifecycle meta-argument
Check your lifecycle block against the complete list of valid Terraform lifecycle arguments:
- create_before_destroy - boolean: Create new resource before destroying old one
- prevent_destroy - boolean: Prevent resource destruction
- ignore_changes - list or 'all': Ignore changes to specific attributes
- replace_triggered_by - list: Replace resource when dependent resource changes
- precondition - block: Check conditions before creating/updating resource
- postcondition - block: Check conditions after lifecycle operations
- action_trigger - block: Automatically invoke actions based on conditions
Correct example:
resource "aws_instance" "example" {
ami = "ami-0c55b159cbfafe1f0"
instance_type = "t2.micro"
lifecycle {
create_before_destroy = true
prevent_destroy = false
ignore_changes = [tags]
}
}Review your lifecycle block carefully for common typos:
Incorrect:
lifecycle {
create_destroy = true # Wrong: should be 'create_before_destroy'
prevent_remove = true # Wrong: should be 'prevent_destroy'
ignore_change = ["tags"] # Wrong: should be 'ignore_changes'
replace_on = [aws_iam_role] # Wrong: should be 'replace_triggered_by'
}Correct:
lifecycle {
create_before_destroy = true
prevent_destroy = true
ignore_changes = ["tags"]
replace_triggered_by = [aws_iam_role.example]
}Ensure you're using the correct block syntax. The lifecycle block should use curly braces { }, not assignment with equals sign.
Incorrect:
resource "aws_instance" "example" {
lifecycle = {
prevent_destroy = true
}
}Correct:
resource "aws_instance" "example" {
lifecycle {
prevent_destroy = true
}
}The lifecycle block does not support variables, dynamic blocks, or conditional values. All lifecycle arguments must be static values.
Incorrect (not supported):
variable "prevent_destroy_enabled" {
type = bool
}
resource "aws_instance" "example" {
lifecycle {
prevent_destroy = var.prevent_destroy_enabled # Variables not allowed!
}
}Correct approach - use separate configurations or modules:
resource "aws_instance" "example" {
lifecycle {
prevent_destroy = true # Must be a literal value
}
}Be careful not to confuse the lifecycle meta-argument with provider-specific lifecycle_policy arguments. Some AWS resources like S3 and EFS have their own lifecycle_policy arguments that are different from the Terraform lifecycle block.
Terraform lifecycle meta-argument (applies to all resources):
resource "aws_instance" "example" {
lifecycle {
prevent_destroy = true
}
}AWS-specific lifecycle_policy (for S3 buckets):
resource "aws_s3_bucket_lifecycle_configuration" "example" {
bucket = aws_s3_bucket.example.id
rule {
id = "rule1"
status = "Enabled"
expiration {
days = 30
}
}
}These are completely different features.
After making corrections, use Terraform's built-in validation command to catch syntax and argument errors early:
terraform validateThis command checks your configuration against Terraform's schema and will report any invalid arguments or syntax issues before you attempt to plan or apply.
If the validation passes, you can safely proceed to planning:
terraform planBlock vs Meta-argument: The lifecycle is a meta-argument, which means it applies to the resource block itself, not as a nested resource configuration. It must appear at the same indentation level as other top-level resource arguments like ami or instance_type.
Nested Block Arguments: Some lifecycle arguments like precondition and postcondition are themselves blocks that contain their own arguments (condition, error_message). Ensure nested block syntax is correct:
lifecycle {
precondition {
condition = var.instance_count > 0
error_message = "Instance count must be greater than 0."
}
}Version Compatibility: The precondition, postcondition, and action_trigger features were added in Terraform 1.4.0. If you're using an older version of Terraform, these arguments won't be recognized. Upgrade Terraform to use these features.
Resource vs Module Scope: The lifecycle meta-argument applies only to resource blocks. You cannot use it in module blocks. Module-level lifecycle control is not yet supported in Terraform.
State Recording: Except for create_before_destroy, Terraform does not record lifecycle rules in the state file. Only create_before_destroy affects the stored state because it's the only lifecycle argument that changes how Terraform stores object metadata.
Error: Error rendering template: template not found
How to fix "template not found" error in Terraform
Error: Error generating private key
How to fix 'Error generating private key' in Terraform
Error creating Kubernetes Service: field is immutable
How to fix "field is immutable" errors in Terraform
Error: Error creating local file: open: permission denied
How to fix "Error creating local file: permission denied" in Terraform
Error: line endings have changed from CRLF to LF
Line endings have changed from CRLF to LF in Terraform