Hi all,

we are running BIND in Red Hat servers. We are using release BIND 
9.8.2rc1-RedHat-9.8.2-0.37.rc1.el6_7.6.

We are not using BIND in an standard Internet environment. Instead, we are 
using BIND in a mobile network environment, in which DNS Root service is 
provided by service providers. Therefore, we are no using built-in root 
servers. So, we have customized the content of db.root file to include IP 
addresses of DNS servers belonging to our service provider. In our case we have 
configuration similar to the following one (we have omitted real server names 
and IP addresses):


. 3600000 IN NS SERVER1.grx.
SERVER1.grx. 3600000 IN A 10.10.10.1

. 3600000 IN NS SERVER2.grx.
SERVER2.grx. 3600000 IN A 10.10.20.1

. 3600000 IN NS SERVER3.grx.
SERVER3.grx. 3600000 IN A 10.10.30.1

. 3600000 IN NS SERVER4.grx.
SERVER4.grx. 3600000 IN A 10.10.40.1

. 3600000 IN NS SERVER5.grx.
SERVER5.grx. 3600000 IN A 10.10.50.1

. 3600000 IN NS SERVER6.grx.
SERVER6.grx. 3600000 IN A 10.10.60.1

We have noticed that each query forwarded towards root servers creates an extra 
NS ROOT query. We have been reading about "root priming", so were expecting 
this NS ROOT query upon server restart. However, we are seeing this kind of 
query for each query that has to be resolved with root servers assistance. We 
believed that "root priming" was supposed to happen once a day or upon ROOT 
SERVER TTL, which in our case is 3600, i.e., our root servers are replying with 
TTL 3600 to NS ROOT queries.

How can we stop/limit these massive NS ROOT queries?

In addition, we are going to configure a second provider that has warned us on 
they do not reply to NS ROOT queries. Could this pose a problem for our DNS 
servers? Is it possible to instruct our DNS servers not to perform root priming?

Thanks for your help.

Kind regards,
Antonio.

P.S. Below you can find the structure of our named.conf file


acl "ExternalACL" {any;};

acl "InternalACL" {10.10.100.1/32;10.10.200.1/32; };

options {

  allow-recursion {10.10.100.1/32;10.10.200.1/32;};
  directory "/var/named";


};


view "InternalView" IN {

  match-clients {InternalACL;};

  allow-recursion {10.10.100.1/32;10.10.200.1/32;};

  zone "." IN {
    type hint;
    file "db.root";
  };

# Master Zone(s):

MASTER ZONES

};

view "ExternalView" IN {
  allow-recursion {127.0.0.1;};
  allow-transfer {none;};
  match-clients {key 
gibraltar-externalview-smkey;!gibraltar-externalview-other-smkeys;ExternalACL;};
  zone "." IN {
    type hint;
    file "db.root";
  };
  # Master Zone(s):
MASTER ZONES
};





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