$TTL 300
$ORIGIN d.qmail.jp.

@   IN SOA a.ns tm.mail 2016080301 86400 14400 259200 3600
    IN MX 10 mail
    IN NS a.ns
    IN NS b.ns
www IN A 127.0.0.1
   IN TXT "Some txt"
mail IN CNAME www
a.ns IN A  192.168.10.7
b.ns IN A  192.168.10.7
c    IN NS d.c
d.c  IN A  192.168.10.7