ところで、sp.2ch.net って何?
Verisignが管理しているGTLD-SERVERS.NETのSOAには、ns[1-3].he.net. しかのってないが、
he.netのSOAには、sp.2ch.net. のレコードがある
しかも、sp.2ch.net のDNS登録内容は激しく間違ってるし情報が古い

# dig @sp.2ch.net 2ch.net axfr

; <<>> DiG 8.4 <<>> @sp.2ch.net 2ch.net axfr
; (1 server found)
$ORIGIN 2ch.net.
@            1D IN SOA    ns root (
                       36       ; serial
                       8H       ; refresh
                       4H       ; retry
                       5w6d16h     ; expiry
                       1D )      ; minimum

            1D IN NS    ns3
            1D IN NS    ns
            1D IN NS    tako.2ch.net
            1D IN NS    home.ohayou.com.
            1D IN A     216.218.139.94
            1D IN MX    10 ns3
            1D IN MX    20 home.ohayou.com.
ns3          1D IN A      202.220.159.157
saki         1D IN A      216.218.132.98
piza         1D IN CNAME  saki.he.net.
tako         1D IN A      210.224.163.192
mentai        1D IN A     216.218.192.138
salad         1D IN A      64.71.140.84
localhost       1D IN A     127.0.0.1
mail         1D IN A      210.230.87.13
www         1D IN CNAME  biwa4.he.net.
irc          1D IN A      210.160.107.117
www2        1D IN A     210.224.163.192
yasai         1D IN A     64.71.133.115
cheese       1D IN A     64.71.137.42
cocoa        1D IN A     64.71.137.42
sports2       1D IN A     210.224.161.33
www3        1D IN A     202.223.57.83
natto         1D IN A     64.71.140.83
ns          1D IN A     210.230.87.13
teri         1D IN A      64.71.133.118
@           1D IN SOA    ns root (
                      36       ; serial
                      8H       ; refresh
                      4H       ; retry
                      5w6d16h     ; expiry
                      1D )      ; minimum

;; Received 28 answers (28 records).
;; FROM: to SERVER: 61.211.226.250
;; WHEN: Wed May 26 20:30:11 2004