流水账: Node DNS 解析异常探究

[bxb100]

前情提要

Local subdomains on macOS with Dnsmasq and Caddy

配置

• dnsmasq 配置 test => 127.0.0.1
• caddy 配置 ll.test => 127.0.0.1:8080
• 启动 http-server

思考过程

网页正常, 插件不正常, 我猜测可能是 DNS 在 fetch 命令下没有生效, 但是查询文档 dns.lookup()^1, 其中有段文字写道

For instance, dns.lookup() will almost always resolve a given name the same way as the ping command

那么我就猜呗

首先 ping ll.test 没 ping 通, 看到 Surge 代理开着, 寻思着有可能是它的问题, 关闭再测试, 还是不通, 最后发现没刷新 DNS 🃏

理理思路, 首先先确定 DNS 有没有起作用, scutil --dns^2 确定自定义的 nameserver 是在 DNS resolver 链里面, 然后查看 nslookup 文档

Interactive mode is entered in the following cases:

   1. when no arguments are given (the default name server
      will be used)

   2. when the first argument is a hyphen (-) and the second
      argument is the host name or Internet address of a
      name server.

那么首先知道 nslookup ll.test 应该要无法解析, 然后才能让后面 nameserver 来 resolver

nslookup ll.test
Server:     198.18.0.2
Address:    198.18.0.2#53

Non-authoritative answer:
Name:   ll.test
Address: 198.18.2.181

又被 Surge gank 了, 关掉之后

nslookup ll.test
Server:     fe80::8ede:f9ff:feb2:4ed%12
Address:    fe80::8ede:f9ff:feb2:4ed%12#53

** server can't find ll.test: NXDOMAIN

然后

nslookup ll.test localhost
Server:     localhost
Address:    ::1#53

Name:   ll.test
Address: 127.0.0.1

再去 Raycast curl 测试就正常了

总结

大部分情况下应该是 DNS 没有刷新或者没启用导致的

[bxb100]

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