ラズベリーパイを使ってみる – DNSサーバへの問い合わせをする!(dig) –

スポンサーリンク

コンテンツ

コマンド一つでかんたんにできます!

コマンドを実行するために必要なソフトのインストール

sudo apt-get install dnsutils

インストール時の様子

sudo apt-get install dnsutils
Reading package lists... Done
Building dependency tree       
Reading state information... Done
The following extra packages will be installed:
  bind9-host libbind9-90 libdns100 libisc95 libisccfg90 liblwres90
Suggested packages:
  rblcheck
The following NEW packages will be installed:
  dnsutils
The following packages will be upgraded:
  bind9-host libbind9-90 libdns100 libisc95 libisccfg90 liblwres90
6 upgraded, 1 newly installed, 0 to remove and 143 not upgraded.
Need to get 1,063 kB of archives.
After this operation, 326 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Get:1 http://mirrordirector.raspbian.org/raspbian/ jessie/main bind9-host armhf 1:9.9.5.dfsg-9+deb8u5 [65.1 kB]
Get:2 http://mirrordirector.raspbian.org/raspbian/ jessie/main libisc95 armhf 1:9.9.5.dfsg-9+deb8u5 [149 kB]
Get:3 http://mirrordirector.raspbian.org/raspbian/ jessie/main libdns100 armhf 1:9.9.5.dfsg-9+deb8u5 [598 kB]
Get:4 http://mirrordirector.raspbian.org/raspbian/ jessie/main libisccfg90 armhf 1:9.9.5.dfsg-9+deb8u5 [49.8 kB]
Get:5 http://mirrordirector.raspbian.org/raspbian/ jessie/main libbind9-90 armhf 1:9.9.5.dfsg-9+deb8u5 [40.7 kB]
Get:6 http://mirrordirector.raspbian.org/raspbian/ jessie/main liblwres90 armhf 1:9.9.5.dfsg-9+deb8u5 [47.3 kB]
Get:7 http://mirrordirector.raspbian.org/raspbian/ jessie/main dnsutils armhf 1:9.9.5.dfsg-9+deb8u5 [113 kB]
Fetched 1,063 kB in 3s (343 kB/s)
(Reading database ... 149326 files and directories currently installed.)
Preparing to unpack .../bind9-host_1%3a9.9.5.dfsg-9+deb8u5_armhf.deb ...
Unpacking bind9-host (1:9.9.5.dfsg-9+deb8u5) over (1:9.9.5.dfsg-9+deb8u3) ...
Preparing to unpack .../libisc95_1%3a9.9.5.dfsg-9+deb8u5_armhf.deb ...
Unpacking libisc95 (1:9.9.5.dfsg-9+deb8u5) over (1:9.9.5.dfsg-9+deb8u3) ...
Preparing to unpack .../libdns100_1%3a9.9.5.dfsg-9+deb8u5_armhf.deb ...
Unpacking libdns100 (1:9.9.5.dfsg-9+deb8u5) over (1:9.9.5.dfsg-9+deb8u3) ...
Preparing to unpack .../libisccfg90_1%3a9.9.5.dfsg-9+deb8u5_armhf.deb ...
Unpacking libisccfg90 (1:9.9.5.dfsg-9+deb8u5) over (1:9.9.5.dfsg-9+deb8u3) ...
Preparing to unpack .../libbind9-90_1%3a9.9.5.dfsg-9+deb8u5_armhf.deb ...
Unpacking libbind9-90 (1:9.9.5.dfsg-9+deb8u5) over (1:9.9.5.dfsg-9+deb8u3) ...
Preparing to unpack .../liblwres90_1%3a9.9.5.dfsg-9+deb8u5_armhf.deb ...
Unpacking liblwres90 (1:9.9.5.dfsg-9+deb8u5) over (1:9.9.5.dfsg-9+deb8u3) ...
Selecting previously unselected package dnsutils.
Preparing to unpack .../dnsutils_1%3a9.9.5.dfsg-9+deb8u5_armhf.deb ...
Unpacking dnsutils (1:9.9.5.dfsg-9+deb8u5) ...
Processing triggers for man-db (2.7.0.2-5) ...
Setting up libisc95 (1:9.9.5.dfsg-9+deb8u5) ...
Setting up libdns100 (1:9.9.5.dfsg-9+deb8u5) ...
Setting up libisccfg90 (1:9.9.5.dfsg-9+deb8u5) ...
Setting up libbind9-90 (1:9.9.5.dfsg-9+deb8u5) ...
Setting up liblwres90 (1:9.9.5.dfsg-9+deb8u5) ...
Setting up bind9-host (1:9.9.5.dfsg-9+deb8u5) ...
Setting up dnsutils (1:9.9.5.dfsg-9+deb8u5) ...
Processing triggers for libc-bin (2.19-18+deb8u1) ...

使い方の例

dig google.co.jp

実行例

pi@raspberrypi:~ $ dig www.google.co.jp

; <<>> DiG 9.9.5-9+deb8u5-Raspbian <<>> www.google.co.jp
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 17293
;; flags: qr rd ra; QUERY: 1, ANSWER: 16, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1280
;; QUESTION SECTION:
;www.google.co.jp.		IN	A

;; ANSWER SECTION:
www.google.co.jp.	61	IN	A	202.224.62.104
www.google.co.jp.	61	IN	A	202.224.62.113
www.google.co.jp.	61	IN	A	202.224.62.84
www.google.co.jp.	61	IN	A	202.224.62.93
www.google.co.jp.	61	IN	A	202.224.62.123
www.google.co.jp.	61	IN	A	202.224.62.109
www.google.co.jp.	61	IN	A	202.224.62.103
www.google.co.jp.	61	IN	A	202.224.62.114
www.google.co.jp.	61	IN	A	202.224.62.94
www.google.co.jp.	61	IN	A	202.224.62.98
www.google.co.jp.	61	IN	A	202.224.62.88
www.google.co.jp.	61	IN	A	202.224.62.89
www.google.co.jp.	61	IN	A	202.224.62.108
www.google.co.jp.	61	IN	A	202.224.62.118
www.google.co.jp.	61	IN	A	202.224.62.99
www.google.co.jp.	61	IN	A	202.224.62.119

;; Query time: 26 msec
;; SERVER: 192.168.1.1#53(192.168.1.1)
;; WHEN: Wed Feb 10 04:01:37 UTC 2016
;; MSG SIZE  rcvd: 301

解説

digはドメイン名(例だとgoogle.co.jp)をDNSサーバに問い合わせ、その結果が表示されています。
上の例だとgoogle.co.jpは202.224.62.104など、多くのIPアドレスと対応付けされていることがわかります。
結果の見方を説明するととても複雑になるので、興味のある方は「DNSサーバ」というキーワードで検索してみるといいかと思います!

ラズベリーパイでネットワークの状態を確認したい時にすごく便利です!