1. watchA
+noedns でないと、FORMERRが返る。
;; WARNING: EDNS query returned status FORMERR - retry with '+noedns'
2. whois
3. history
$ dig -t a microsoft-com.mail.protection.outlook.com @ns2-proddns.glbdns.o365filtering.com +noedns ; <<>> DiG 9.11.3-1ubuntu1.14-Ubuntu <<>> -t a microsoft-com.mail.protection.outlook.com @ns2-proddns.glbdns.o365filtering.com +noedns ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 18210 ;; flags: qr aa rd; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 0 ;; WARNING: recursion requested but not available ;; QUESTION SECTION: ;microsoft-com.mail.protection.outlook.com. IN A ;; ANSWER SECTION: microsoft-com.mail.protection.outlook.com. 10 IN A 40.93.207.1 microsoft-com.mail.protection.outlook.com. 10 IN A 52.101.24.0 microsoft-com.mail.protection.outlook.com. 10 IN A 40.93.212.0 microsoft-com.mail.protection.outlook.com. 10 IN A 40.93.207.0 ;; Query time: 239 msec ;; SERVER: 104.47.72.81#53(104.47.72.81) ;; WHEN: Sun Sep 19 08:08:24 JST 2021 ;; MSG SIZE rcvd: 287