Unable to create global database using Terraform

[jroy]

I am trying to create an Aurora MySQL database using the following module-

resource "aws_rds_global_cluster" "rdsglobal" {

  provider                  = "aws.primary"

  

  global_cluster_identifier = "${var.global_database_id}"

  storage_encrypted         = "${var.storage_encrypted}"

}

resource "aws_rds_cluster_instance" "primary" {

  provider                  = "aws.primary"

  count                     = "${var.instance_count}"

  identifier                = "${var.db_name}-${count.index+1}"

  cluster_identifier        = "${aws_rds_cluster.primary.id}"

  instance_class            = "${var.instance_class}"

  engine                    = "${var.engine}"

  engine_version            = "${var.engine_version}"

  publicly_accessible       = "${var.publicly_accessible}"

}

resource "aws_rds_cluster" "primary" {

  provider                  = "aws.primary"

  cluster_identifier        = "${var.primary_cluster_id}"

  database_name             = "${var.db_name}"

  port                      = "${var.port}"

  engine                    = "${var.engine}"

  engine_version            = "${var.engine_version}"

  master_username           = "${var.master_username}"

  master_password           = "${random_string.password.result}"

  vpc_security_group_ids    = ["${var.security_group_ids}"] 

  db_subnet_group_name      = "${var.db_subnet_group_name}" 

  storage_encrypted         = "${var.storage_encrypted}"

  backup_retention_period   = "${var.backup_retention_period}"

  skip_final_snapshot       = "${var.skip_final_snapshot}"

  engine_mode               = "${var.engine_mode}"

  global_cluster_identifier = "${aws_rds_global_cluster.rdsglobal.id}"

}

resource "aws_rds_cluster_instance" "secondary" {

  provider                  = "aws.secondary"

  count                     = "${var.instance_count}"

  identifier                = "${var.db_name}-${count.index+1}"

  cluster_identifier        = "${aws_rds_cluster.secondary.id}"

  instance_class            = "${var.instance_class}"

  engine                    = "${var.engine}"

  engine_version            = "${var.engine_version}"

  publicly_accessible       = "${var.publicly_accessible}"

}

resource "aws_rds_cluster" "secondary" {

  depends_on                = ["aws_rds_cluster_instance.primary"]

  provider                  = "aws.secondary"

  cluster_identifier        = "${var.secondary_cluster_id}"

  port                      = "${var.port}"

  engine                    = "${var.engine}"

  engine_version            = "${var.engine_version}"

  master_username           = "${var.master_username}"

  master_password           = "${random_string.password.result}"

  vpc_security_group_ids    = ["${var.secondary_security_group_ids}"] 

  db_subnet_group_name      = "${var.db_subnet_group_name}" 

  engine_mode               = "${var.engine_mode}"

  global_cluster_identifier = "${aws_rds_global_cluster.rdsglobal.id}"

}

The primary cluster gets created but the secondary cluster throws the following error-

Error: Error applying plan:

1 error(s) occurred:

* aws_rds_cluster.secondary: 1 error(s) occurred:

* aws_rds_cluster.secondary: error creating RDS cluster: InvalidParameterCombination: Cannot specify user name for cross region replication cluster

status code: 400, request id: 10b82a78-898c-49e6-b28f-0a318fdc226f

I tried by removing the following line- 

master_username           = "${var.master_username}"

I got the below error-

Error: Error applying plan:

1 error(s) occurred:

* aws_rds_cluster.secondary: 1 error(s) occurred:

* aws_rds_cluster.secondary: provider.aws: aws_rds_cluster: : "master_username": required field is not set

Any help will be greatly appreciated.

Thanks!

[brad.cu...@sendgrid.com]

I've fixed this in https://github.com/terraform-providers/terraform-provider-aws/pull/7213 but it is not reviewed or merged.

Brad