root hint for subdomain how to.

[Truong Tan Son]

Dear Sir,

I install Bind9.2 on RedHat Linux, I create one main DNS server, and one subdomain server.

On main server "domain.com"
#/etc/named.conf
options {
        directory "/usr/local/named/etc";
          };

controls {
        inet 127.0.0.1 allow { localhost; } keys { rndckey; };
        };

zone "." IN {
        type hint;
        file "named.ca";
};
......
......
zone "domain.com" IN {
        type master;
        file "domain.com.db";
};

#/etc/named/domain.com
@ IN SOA root1.domain.com. admin.domain.com. (
1;
10800;
3600;
604800;
86400 );
                                              IN NS   root1.domain.com.
root1                                      IN A 172.16.20.11

info.domain.com.                    IN NS server1.info.domain.com.
sercer1.info.domain.com.        IN A 172.16.134.10


On subdomain server "info.domain.com", I defined:
#/etc/named.conf
zone ".domain.com." IN {
        type hint;
        file "named.ca";
};

#/var/named/named.ca
.domain.com.              NS      root1.domain.com.
root1.domain.com.        A        172.16.20.11

Does HINT for subdomain correct ?

Please help me to solve this trouble

Thanks you and best regards,
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