DNS/unbound/harden-referral-path/sampleについて、ここに記述してください。

ubuntu 14.04 にのせた unbound (1.4.22?)で

$ dig -t ns vv.qmail.jp 

; <<>> DiG 9.9.5-3ubuntu0.1-Ubuntu <<>> -t ns vv.qmail.jp
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 13737
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 2

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;vv.qmail.jp.                   IN      NS

;; ANSWER SECTION:
vv.qmail.jp.            345600  IN      NS      a.ns.vv.qmail.jp.

;; ADDITIONAL SECTION:
a.ns.vv.qmail.jp.       345600  IN      A       14.192.44.29

;; Query time: 331 msec
;; SERVER: 127.0.0.1#53(127.0.0.1)
;; WHEN: Thu Dec 18 08:49:03 JST 2014
;; MSG SIZE  rcvd: 75

1. off 時

Dec 18 08:49:02 tmaeno unbound: [1062:0] info: resolving vv.qmail.jp. NS IN
Dec 18 08:49:02 tmaeno unbound: [1062:0] info: response for vv.qmail.jp. NS IN
Dec 18 08:49:02 tmaeno unbound: [1062:0] info: reply from <jp.> 156.154.100.5#53
Dec 18 08:49:02 tmaeno unbound: [1062:0] info: query response was REFERRAL
Dec 18 08:49:02 tmaeno unbound: [1062:0] info: response for vv.qmail.jp. NS IN
Dec 18 08:49:02 tmaeno unbound: [1062:0] info: reply from <qmail.jp.> 14.192.44.5#53
Dec 18 08:49:02 tmaeno unbound: [1062:0] info: query response was REFERRAL
Dec 18 08:49:03 tmaeno unbound: [1062:0] info: response for vv.qmail.jp. NS IN
Dec 18 08:49:03 tmaeno unbound: [1062:0] info: reply from <vv.qmail.jp.> 14.192.44.29#53
Dec 18 08:49:03 tmaeno unbound: [1062:0] info: query response was ANSWER

2. on

server:
        verbosity: 2
        harden-referral-path: yes
        do-ip6: no
        do-udp: yes
        cache-min-ttl: 1800
#        tcp-upstream: yes

dig-vv