如何只返回非大陆IP

[4thanks]

以下哪种配置是比较合理呢？能否实现只返回非大陆IP

1. _drop_response丢掉返回的应答IP？这里是不是本次解析也一并丢弃，给下一个sequence解析？

  - tag: ""
    type: "sequence"
    args:
      exec:
        - forward_google
        - if: (response_has_local_ip)
        - exec:
            - _drop_response

2. _return返回再次解析？

  - tag: ""
    type: "sequence"
    args:
      exec:
        - forward_google
        - if: (! response_has_local_ip)
        - exec:
            - _return

3. if & else双重条件，这种方式大概可能返回IP是被和谐，重复解析直到有效IP？

  - tag: ""
    type: "sequence"
    args:
      exec:
        - forward_google
        - if: (response_has_local_ip)
        - exec:
            - _drop_response
        - else_exec:
            - _return

4. 如果是fallback多组dns应该怎么配置？

- tag: ""
  type: "sequence"
  args:
    exec:
      - primary:            
          - "ecs_1"
          - "forward_1"
        secondary:          
          - "ecs_2"
          - "forward_2"   
        fast_fallback: 200  
        always_standby: true