443 端口是 DOH ,nslookup 不支持;
8.8.8.8 的 53 端口能支持 tcp 查询:
dig +tcp @
8.8.8.8
google.com; <<>> DiG 9.18.39-0ubuntu0.22.04.2-Ubuntu <<>> +tcp @
8.8.8.8
google.com; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 48017
;; flags: qr rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;
google.com. IN A
;; ANSWER SECTION:
google.com. 166 IN A 74.125.24.100
google.com. 166 IN A 74.125.24.102
google.com. 166 IN A 74.125.24.113
google.com. 166 IN A 74.125.24.101
google.com. 166 IN A 74.125.24.139
google.com. 166 IN A 74.125.24.138
;; Query time: 1 msec
;; SERVER: 8.8.8.8#53(8.8.8.8) (TCP)
;; WHEN: Tue Dec 16 09:24:52 HKT 2025
;; MSG SIZE rcvd: 135