基本的に何が出来るものか、というとnslookupと同じで名前を引くツール。 名前を引く †nslookupと同じように名前を引くことが出来る。 【dig】 # dig google.com ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6_3.6 <<>> google.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 51157 ;; flags: qr rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 4, ADDITIONAL: 4 ;; QUESTION SECTION: ;google.com. IN A ;; ANSWER SECTION: google.com. 300 IN A 74.125.31.113 google.com. 300 IN A 74.125.31.138 google.com. 300 IN A 74.125.31.139 google.com. 300 IN A 74.125.31.100 google.com. 300 IN A 74.125.31.101 google.com. 300 IN A 74.125.31.102 ;; AUTHORITY SECTION: google.com. 165385 IN NS ns1.google.com. google.com. 165385 IN NS ns4.google.com. google.com. 165385 IN NS ns3.google.com. google.com. 165385 IN NS ns2.google.com. ;; ADDITIONAL SECTION: ns2.google.com. 165385 IN A 216.239.34.10 ns1.google.com. 165385 IN A 216.239.32.10 ns3.google.com. 165385 IN A 216.239.36.10 ns4.google.com. 165385 IN A 216.239.38.10 ;; Query time: 331 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Mon Jan 27 13:35:55 2014 ;; MSG SIZE rcvd: 260 【nslookup】 # nslookup google.com Server: 127.0.0.1 Address: 127.0.0.1#53 Non-authoritative answer: Name: google.com Address: 74.125.31.138 Name: google.com Address: 74.125.31.139 Name: google.com Address: 74.125.31.100 Name: google.com Address: 74.125.31.101 Name: google.com Address: 74.125.31.102 Name: google.com Address: 74.125.31.113
ネームサーバを指定 †これもnslookupにあった機能だが、当然digにも存在する。 # dig @[nameserver] [対象ドメイン] # dig @127.0.0.1 google.com ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.10.rc1.el6_3.6 <<>> @127.0.0.1 google.com ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 45318 ;; flags: qr rd ra; QUERY: 1, ANSWER: 6, AUTHORITY: 4, ADDITIONAL: 4 ;; QUESTION SECTION: ;google.com. IN A ;; ANSWER SECTION: google.com. 119 IN A 74.125.31.139 google.com. 119 IN A 74.125.31.100 google.com. 119 IN A 74.125.31.101 google.com. 119 IN A 74.125.31.102 google.com. 119 IN A 74.125.31.113 google.com. 119 IN A 74.125.31.138 ;; AUTHORITY SECTION: google.com. 165204 IN NS ns3.google.com. google.com. 165204 IN NS ns1.google.com. google.com. 165204 IN NS ns2.google.com. google.com. 165204 IN NS ns4.google.com. ;; ADDITIONAL SECTION: ns2.google.com. 165204 IN A 216.239.34.10 ns1.google.com. 165204 IN A 216.239.32.10 ns3.google.com. 165204 IN A 216.239.36.10 ns4.google.com. 165204 IN A 216.239.38.10 ;; Query time: 0 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Mon Jan 27 13:38:56 2014 ;; MSG SIZE rcvd: 260 DNSのスレーブ転送をチェックする †使用方法は # dig @[マスターサーバ] [対象ドメイン] [オプション] # dig @49.212.182.151 jitaku-svr.info axfr ; <<>> DiG 9.9.3-P2 <<>> @49.212.182.151 jitaku-svr.info axfr ; (1 server found) ;; global options: +cmd jitaku-svr.info. 86400 IN SOA ns01.jitaku-svr.info. root.jitaku-svr.info. 2014010800 10800 3600 604800 86400 jitaku-svr.info. 86400 IN NS ns01.jitaku-svr.info. jitaku-svr.info. 86400 IN NS ns02.jitaku-svr.info. jitaku-svr.info. 86400 IN MX 10 ml.jitaku-svr.info. jitaku-svr.info. 86400 IN MX 10 check.jitaku-svr.info. jitaku-svr.info. 86400 IN A 49.212.182.151 check.jitaku-svr.info. 86400 IN TXT "v=spf1 +ip4:27.120.106.76/32 ~all" check.jitaku-svr.info. 86400 IN A 27.120.106.76 _adsp._domainkey.check.jitaku-svr.info. 86400 IN TXT "dkim=unknown" default._domainkey.check.jitaku-svr.info. 86400 IN TXT "v=DKIM1\; k=rsa\; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCz1RVADO3Nuwx0R4PUkA0W4XfbtPbxEeFkWQKW6f2XieNGqSW01//kZWOIg+3UCvgXYzI54Snlf6TaKdkpxEPVsWyNDQO2BT6qC8s/TKHmEV7sxDpsF8c586KOm6LAPI8tT3iVxFBnYPZ617Wcw/JPW9L0h+txqVQlr8D5Dvx7rQIDAQAB" ml.jitaku-svr.info. 86400 IN A 49.212.182.151 ml.jitaku-svr.info. 86400 IN TXT "v=spf1 +ip4:49.212.182.151/32 ~all" _adsp._domainkey.ml.jitaku-svr.info. 86400 IN TXT "dkim=unknown" default._domainkey.ml.jitaku-svr.info. 86400 IN TXT "v=DKIM1\; k=rsa\; p=MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCvDkdKXJwnP9MbexVaReKOkfltTHLR/6JUfmNg33TXxkxa/7XR9IEQVPZlL7zQS3XXqNgv8/UC8dzDdhsA1kn7jpcEJbVC3Pg4hIgFbk9hnMZrbJLIDo/9RPzsOdm99PwY8+hzrBJH6K9q3806RIxLGI0R0FjaWsyQnOLcfwiccQIDAQAB" ns01.jitaku-svr.info. 86400 IN A 49.212.182.151 ns02.jitaku-svr.info. 86400 IN A 27.120.106.76 www.jitaku-svr.info. 86400 IN CNAME ns01.jitaku-svr.info. jitaku-svr.info. 86400 IN SOA ns01.jitaku-svr.info. root.jitaku-svr.info. 2014010800 10800 3600 604800 86400 ;; Query time: 30 msec ;; SERVER: 49.212.182.151#53(49.212.182.151) ;; WHEN: Mon Jan 27 13:44:08 JST 2014 ;; XFR size: 18 records (messages 1, bytes 974) 上記のように成功した場合はログが表示される。 パケットサイズを調べる †これは以前qmailを使用している環境で起きた現象だが、qmailが名前解決をするときに、DNSへの問い合わせは通常udpによる通信をする。 qmailには512バイトを越える通信の場合、デフォルトだとエラーになってしまうバグがあるため(バッチは配布済み) # dig google.com ~~~省略~~~ ;; MSG SIZE rcvd: 260 このMSGサイズという箇所。 |