1. DNS/flag_day/2020/dns-oarc/ISPリゾルバー

テスト例:  dig +bufsize=1024 rs.dns-oarc.net TXT @1.1.1.1

/さくらが大きいままで、危険です。 -- ToshinoriMaeno 2020-10-06 21:47:56

nifty      202.248.37.74 / 202.248.20.133  : 512
ntt.net    129.250.35.250 / 129.250.35.251 : 512
IIJ        210.130.0.1 / 210.130.1.1       : 1220
IIJ        202.232.2.38 / 202.232.2.39     : 1220
nuro.jp    118.238.201.33                  : 512
so-net.jp  202.238.95.24                   : 512             
cdn-japan.com  210.130.232.1               : 1220
sakura     210.188.224.10                  : 4096
sakura     210.224.163.3    /4             : 4096

$ dig +bufsize=1024 rs.dns-oarc.net TXT @210.188.224.10

; <<>> DiG 9.11.3-1ubuntu1.12-Ubuntu <<>> +bufsize=1024 rs.dns-oarc.net TXT @210.188.224.10
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35420
;; flags: qr rd ra; QUERY: 1, ANSWER: 5, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;rs.dns-oarc.net.               IN      TXT

;; ANSWER SECTION:
rs.dns-oarc.net.        59      IN      CNAME   rst.x4050.rs.dns-oarc.net.
rst.x4050.rs.dns-oarc.net. 58   IN      CNAME   rst.x4060.x4050.rs.dns-oarc.net.
rst.x4060.x4050.rs.dns-oarc.net. 58 IN  CNAME   rst.x4066.x4060.x4050.rs.dns-oarc.net.
rst.x4066.x4060.x4050.rs.dns-oarc.net. 57 IN TXT "2001:e42:100::11 DNS reply size limit is at least 4066"
rst.x4066.x4060.x4050.rs.dns-oarc.net. 57 IN TXT "2001:e42:100::11 sent EDNS buffer size 4096"

;; Query time: 1523 msec
;; SERVER: 210.188.224.10#53(210.188.224.10)
;; WHEN: Fri Oct 02 15:30:48 JST 2020
;; MSG SIZE  rcvd: 239