peering_simple.tf

module vpc_a {
  source  = "terraform-aws-modules/vpc/aws"
}
 
module vpc_b {
  source  = "terraform-aws-modules/vpc/aws"
  
  # マルチアカウントなので別のAWSアカウントを指定
  providers = {
    aws = aws.b
  }
}
  
# AからBへ繋がりたい
resource aws_vpc_peering_connection a_to_b {
  peer_owner_id = module.vpc_b.vpc_id.vpc_owner_id
  peer_vpc_id   = module.vpc_b.vpc_id
  vpc_id        = module.vpc_a.vpc_id
  auto_accept   = false
}

# BからAへ繋がり許可
resource aws_vpc_peering_connection_accepter b_to_a {
  provider                  = aws.b
  vpc_peering_connection_id = aws_vpc_peering_connection.a_to_b.id
  auto_accept               = true
}
       
# B側でリソースの設定変更する
resource aws_vpc_peering_connection_options ｂ {
  provider = aws.ｂ

  vpc_peering_connection_id = aws_vpc_peering_connection.a_to_b.id

  accepter {
    allow_remote_vpc_dns_resolution = true
  }
}