How to set different failover priority to nodes AWS Aurora cluster


I am working on creating a template for Aurora RDS clusters using terraform, RDS clusters will be global multi-AZ with 3 nodes in primary region and 2 nodes in secondary region.

passing value for “promotion_tier” will set the failover priority but it is going to be same for all nodes.

I am looking for a way to set different failover priority for 3 nodes in primary region, can this be accomplished with terraform.

Code block from

resource "aws_rds_cluster_instance" "default" {
  count                   = "${local.enabled ? var.cluster_size : 0}"
  identifier              = "${}-${count.index+1}"
  cluster_identifier      = "${var.cluster_identifier}"
  engine                  = "${local.engine}"
  instance_class          = "${var.instance_type}"
  db_subnet_group_name    = "${local.db_subnet_group_name}"
  db_parameter_group_name = "${join("", aws_db_parameter_group.default.*.name)}"
  publicly_accessible     = "${var.publicly_accessible}"
  promotion_tier          = "${var.promotion_tier}"
  tags                    = "${module.label.tags}"
  monitoring_interval     = "${var.rds_monitoring_interval}"
  monitoring_role_arn     = "${var.rds_monitoring_role_arn}"

code block from

variable "promotion_tier" {
  description = "Failover Priority setting on instance level. The reader who has lower tier has higher priority to get promoted to writer (values can range from 0-15)."
  default     = "2"