Terraform 已定义地形额外路线

我在tf状态文件中看到了这一点-

 "schema_version": 0,
          "attributes": {
            "id": "rtbassoc-0ac72627f041ceccf",
            "original_route_table_id": "rtb-0ebfd5599c2564b64",
            "route_table_id": "rtb-0ea661cb53a2e8f0a",
            "vpc_id": "vpc-055602c40c4dc09dc"

为什么要添加两个路由表？这似乎导致我无法连接到实例

resource "aws_internet_gateway" "gw" {
  vpc_id = aws_vpc.UAT-vpc.id
}

resource "aws_route_table" "rt" {
  vpc_id = aws_vpc.UAT-vpc.id

  route {
  cidr_block = "0.0.0.0/0"
  gateway_id = aws_internet_gateway.gw.id
  }

}

resource "aws_main_route_table_association" "a" {
  vpc_id = aws_vpc.UAT-vpc.id
  route_table_id = aws_route_table.rt.id
}