How to Enable Multi-AZ on the Elasticache Globaldatastore secondary replication group?

Terraform Providers AWS
1

I created a Primary Replication Group in Elasticache and registered it in the global replication group. Up to this point, there was no problem at all.

However, when creating and registering a Secondary Replication Group, I encountered a situation where I could not activate the Multi-AZ option.

To activate the Multi-AZ option, you need to set automatic_failover_enabled = true.

However, if you specify this option in the Secondary Replication Group Resource, it conflicts with the global_replication_group_id option.

How can I activate Multi-AZ in the Secondary Replication Group as well?

# Elasticache Global Datastore
# ========================================================
resource "aws_elasticache_global_replication_group" "global_datastore" {
  provider = aws.primary

  global_replication_group_id_suffix = var.cache.global.name_suffix

  primary_replication_group_id = aws_elasticache_replication_group.primary-elasticache.id
  engine_version               = var.cache.global.engine_version
}


# Primary Elasticache
# ========================================================
resource "aws_elasticache_replication_group" "primary-elasticache" {
  provider = aws.primary

  replication_group_id = var.cache.primary.name
  description          = "Elasticache ${var.cache.primary.name}"

  engine         = var.cache.primary.engine
  engine_version = var.cache.primary.engine_version

  cluster_mode = "enabled"

  node_type               = var.cache.primary.node_type
  num_node_groups         = var.cache.primary.nodegroup_count
  replicas_per_node_group = var.cache.primary.replicas_per_nodegroup

  port = var.cache.primary.port

  subnet_group_name  = aws_elasticache_subnet_group.primary_cache_subnet_group.name
  security_group_ids = [aws_security_group.primary_cache_security_group.id]

  multi_az_enabled           = true
  automatic_failover_enabled = true

  at_rest_encryption_enabled = true
  kms_key_id                 = aws_kms_key.primary-elasticache-cmk.id
  transit_encryption_enabled = true
  transit_encryption_mode    = "required"

  snapshot_retention_limit = var.cache.primary.snapshot_retention_limit

  log_delivery_configuration {
    log_type         = "slow-log"
    log_format       = "json"
    destination_type = "cloudwatch-logs"
    destination      = aws_cloudwatch_log_group.primary_slow-log-log_group.name
  }

  log_delivery_configuration {
    log_type         = "engine-log"
    log_format       = "json"
    destination_type = "cloudwatch-logs"
    destination      = aws_cloudwatch_log_group.primary_engine-log-log_group.name
  }

  apply_immediately = true
}


# Secondary Elasticache
# ========================================================
resource "aws_elasticache_replication_group" "secondary-elasticache" {
  provider = aws.secondary

  global_replication_group_id = aws_elasticache_global_replication_group.global_datastore.id

  replication_group_id = var.cache.secondary.name
  description          = "Elasticache ${var.cache.secondary.name}"

  subnet_group_name  = aws_elasticache_subnet_group.secondary_cache_subnet_group.name
  security_group_ids = [aws_security_group.secondary_cache_security_group.id]

  port = var.cache.secondary.port

  kms_key_id = aws_kms_key.secondary-elasticache-cmk.id

  snapshot_retention_limit = var.cache.secondary.snapshot_retention_limit

  log_delivery_configuration {
    log_type         = "slow-log"
    log_format       = "json"
    destination_type = "cloudwatch-logs"
    destination      = aws_cloudwatch_log_group.secondary_slow-log-log_group.name
  }

  log_delivery_configuration {
    log_type         = "engine-log"
    log_format       = "json"
    destination_type = "cloudwatch-logs"
    destination      = aws_cloudwatch_log_group.secondary_engine-log-log_group.name
  }

  apply_immediately = true
}