June 2016
Beginner to intermediate
376 pages
8h 58m
Japanese
Content preview from データ分析によるネットワークセキュリティ
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
8.3
DNS
171
flags
応答に情報を付加する。
qr
（応答の場合にオンに設定される）、
aa
（答えが権威ネームサーバ
から来た場合にオンに設定される）、
rd
（再帰希望）、
ra
（再帰可能）が入る。
残りの4つのフィールドは、応答で送信されたレコードの種類を示す。以下にその4 つを示す。
QUERY
このレコードは単に元のリクエストのコピーである。この場合、
dig
の
QUESTION
セクション
に
問い合わせ
がコピーされているのがわかる。
ANSWER
応答が入る。
AUTHORITY
他のサーバを特定するレコードのために予約されている。
ADDITIONAL
追加情報を提供する。今後の
問い合わせ
で考えられる応答など。
追加情報は、ネームサーバの管理者に非常に左右される。一般的な使い方の例を以下に示す。こ
の例では、MX問い合わせの返答となるメールサーバの名前検索を提供している。
$ dig +nostats +nocmd mx cmu.edu
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 30852
;; flags: qr rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 3
;; QUESTION SECTION:
;cmu.edu. IN MX
;; ANSWER SECTION:
cmu.edu. 20051 IN MX 10 CMU-MX-02.ANDREW.cmu.edu. ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.