smartdns只返回一个ip容易遇到单点故障（smartdns encounter a single point of failure）

[hupong]

问题现象
我有一个网站部署在多台服务器，所以域名也是解析到了两台机器。今天其中一台出现问题，我用了smartdns，当我用域名访问的时候正好被解析到有问题的那台机器，所以无法访问网站，而别人没有用smartdns就能正常访问。我用nslookup检查发现我的电脑解析的结果是一个ip，而且刚好是有问题（问题是后台服务挂了，nginx还在线）的那台的ip，而别人的电脑解析的结果是多个ip。

I have a website deployed on multiple servers, so the domain name is also resolved to two machines. Today, there was a problem with one of them. I used smartdns. When I accessed it with the domain name, it happened to be resolved to the machine with the problem, so I couldn't access the website, and others could access it normally without using smartdns. I checked with nslookup and found that the result of my computer analysis was an ip address, and it happened to be the ip address of the one with the problem (the problem was that the background service was hung up and nginx was still online), while the result of other people's computer analysis was multiple ip addresses.

运行环境

1. 固件型号
   Windows 10

2. 涉及的配置(注意去除个人相关信息)
   server-name smartdns
   bind :52 -force-aaaa-soa -no-dualstack-selection
   speed-check-mode tcp:80,tcp:443
   response-mode first-ping
   cache-size 32768
   cache-persist yes
   cache-file C:\ProgramData\smartdns\smartdns.cache
   cache-checkpoint-time 10
   rr-ttl 30
   rr-ttl-min 10
   rr-ttl-max 30
   rr-ttl-reply-max 30
   log-level info
   log-file C:\ProgramData\smartdns\smartdns.log
   audit-enable yes
   audit-file C:\ProgramData\smartdns\smartdns-audit.log
   prefetch-domain yes
   serve-expired yes
   server 114.114.114.114

重现步骤

1. 上游DNS配置。
   114.114.114.114

2. 访问的域名。
   内部项目域名不方便公开。
   Internal project domain name is not convenient to disclose.

[PikuZheng]

smartdns does not support Windows