random subdomain block
The Open Source Geospatial Foundation
https://osgeo.org -> https://www.osgeo.org
www.osgeo.org. 432000 IN CNAME web.osgeo9.osgeo.org.
web.osgeo9.osgeo.org. 432000 IN A 140.211.15.13
サブドメインはすべて返答しないような感じもする。
1. whois
osgeo.org. 432000 IN NS NS2.PAIRNIC.COM. osgeo.org. 432000 IN NS NS1.PAIRNIC.COM.
2. history
$ dig -t a randomsubdom.osgeo.org @ns1.pairnic.com ;; communications error to 216.92.3.91#53: timed out ;; communications error to 216.92.3.91#53: timed out ;; communications error to 216.92.3.91#53: timed out ;; UDP setup with 2607:f440::d85c:35b#53(2607:f440::d85c:35b) for randomsubdom.osgeo.org failed: network unreachable.
$ dig -t a web.osgeo9.osgeo.org @ns1.pairnic.com ;; communications error to 216.92.3.91#53: timed out ;; communications error to 216.92.3.91#53: timed out ;; communications error to 216.92.3.91#53: timed out ;; UDP setup with 2607:f440::d85c:35b#53(2607:f440::d85c:35b) for web.osgeo9.osgeo.org failed: network unreachable.
$ dig -t a www.osgeo.org @8.8.8.8
; <<>> DiG 9.18.12-0ubuntu0.22.04.1-Ubuntu <<>> -t a www.osgeo.org @8.8.8.8
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: SERVFAIL, id: 42924
;; flags: qr rd ra; QUERY: 1, ANSWER: 0, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
; NSID: 67 70 64 6e 73 2d 6e 72 74 ("gpdns-nrt")
;; QUESTION SECTION:
;www.osgeo.org. IN A
;; Query time: 2008 msec
;; SERVER: 8.8.8.8#53(8.8.8.8) (UDP)
;; WHEN: Fri May 19 05:15:09 JST 2023
;; MSG SIZE rcvd: 55