DNS secundário - problema

Boa tarde pessoal.
Estou tendo problemas com o meu DNS secundário. Quando eu faço uma verificação de DNS, através do Registro.br, aparece erro de time-out para o meu DNS secundário.
Gostaria de saber se alguém poderia me ajudar.

Abaixo estou postando o named.conf do meu DNS secundário.

//
// named.conf for Red Hat caching-nameserver
//
options {
directory "/usr/local/named/var";
version "n/d";
allow-transfer {
<ip_dns_pri>;
<ip_dns_sec>;
};
allow-recursion {
127.0.0.1;
<rede_interna>;
<rede_dmz>
};
/*
* If there is a firewall between you and nameservers you want
* to talk to, you might need to uncomment the query-source
* directive below. Previous versions of BIND always asked
* questions using port 53, but BIND 8.1 uses an unprivileged
* port by default.
*/
// query-source address * port 53;
};
logging {
category lame-servers { null; };
};
//
// a caching only nameserver config
//
controls {
inet 127.0.0.1 allow { localhost; } keys { rndckey; };
};
zone "." IN {
type hint;
file "named.ca";
};

zone "0.0.127.in-addr.arpa" IN {
type master;
file "0.0.127.in-addr.arpa.zone";
};
zone "xxx-xxx.xxx.xxx.200.in-addr.arpa" IN {
type slave;
file "xxx.xxx.200.in-addr.arpa.zone";
masters { <ip_dns_pri> ;};
};
zone "localhost" IN {
type master;
file "localhost.zone";
};
zone "dominio.com.br" IN {
type slave;
file "dominio.com.br.zone";
masters { <ip_dns_pri> ;};
};
zone "dominio.com" IN {
type slave;
file "dominio.com.br.zone";
masters { <ip_dns_pri> ;};
};
include "/usr/local/named/etc/rndc.key";

Abaixo o /var/log/messages quando eu inicio o DNS secundário.

Feb 7 14:35:30 ns2 named[2070]: starting BIND 9.4.2
Feb 7 14:35:30 ns2 named[2070]: loading configuration from '/usr/local/named/etc/named.conf'
Feb 7 14:35:30 ns2 named[2070]: listening on IPv4 interface lo, 127.0.0.1#53
Feb 7 14:35:30 ns2 named[2070]: listening on IPv4 interface eth0, <ip_dns_sec>#53
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 127.IN-ADDR.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 254.169.IN-ADDR.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 2.0.192.IN-ADDR.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 255.255.255.255.IN-ADDR.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.IP6.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 1.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.IP6.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: D.F.IP6.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 8.E.F.IP6.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: 9.E.F.IP6.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: A.E.F.IP6.ARPA
Feb 7 14:35:30 ns2 named[2070]: automatic empty zone: B.E.F.IP6.ARPA
Feb 7 14:35:30 ns2 named[2070]: command channel listening on 127.0.0.1#953
Feb 7 14:35:30 ns2 named[2070]: zone 0.0.127.in-addr.arpa/IN: loaded serial 2
Feb 7 14:35:30 ns2 named[2070]: zone xxx-xxx.xxx.xxx.200.in-addr.arpa/IN: loaded serial 2007081701
Feb 7 14:35:30 ns2 named[2070]: zone dominio.com.br/IN: loaded serial 2008011601
Feb 7 14:35:30 ns2 named[2070]: dominio.com.br.zone:3: SOA record not at top of zone (dominio.com.br)
Feb 7 14:35:30 ns2 named[2070]: zone dominio.com/IN: loading from master file dominio.com.br.zone failed: not at top of zone
Feb 7 14:35:30 ns2 named[2070]: zone dominio.com/IN: saved 'dominio.com.br.zone' as 'db-TlLPsDiL'
Feb 7 14:35:30 ns2 named[2070]: zone localhost/IN: loaded serial 42
Feb 7 14:35:30 ns2 named[2070]: running
Feb 7 14:35:30 ns2 named[2070]: zone xxx-xxx.xxx.xxx.200.in-addr.arpa/IN: sending notifies (serial 2007081701)
Feb 7 14:35:30 ns2 named[2070]: zone dominio.com.br/IN: sending notifies (serial 2008011601)
Feb 7 14:35:30 ns2 named[2070]: zone dominio.com/IN: Transfer started.
Feb 7 14:35:30 ns2 named[2070]: transfer of 'dominio.com/IN' from <ip_dns_pri>#53: connected using <ip_dns_sec>#56312
Feb 7 14:35:30 ns2 named[2070]: zone dominio.com/IN: transferred serial 2008011601
Feb 7 14:35:30 ns2 named[2070]: transfer of 'dominio.com/IN' from <ip_dns_pri>#53: end of transfer
Feb 7 14:35:30 ns2 named[2070]: zone dominio.com/IN: sending notifies (serial 2008011601)