bind配置的dns服务器，解析正常但是nslookup 默认服务器是unknown

Question

配置如下：

#named.conf

options {
    listen-on port 53 { any; };
    listen-on-v6 port 53 { none; };
    directory     "/var/named";
    dump-file     "/var/named/data/cache_dump.db";
    statistics-file "/var/named/data/named_stats.txt";
    memstatistics-file "/var/named/data/named_mem_stats.txt";
    allow-query     { any; };
    recursion no;

    dnssec-enable yes;
    dnssec-validation yes;

    /* Path to ISC DLV key */
    bindkeys-file "/etc/named.iscdlv.key";

    managed-keys-directory "/var/named/dynamic";

    pid-file "/run/named/named.pid";
    session-keyfile "/run/named/session.key";
    forward only;
    forwarders { 223.6.6.6; };
};

logging {
        channel default_debug {
                file "data/named.run";
                severity dynamic;
        };
};

zone "." IN {
    type hint;
    file "named.ca";
};

zone "qiso.it" IN {
    type master;
    file "qiso.it.zone";
};

zone "120.10.in-addr.arpa" {
    type master;
    file "120.10.zone";
};

include "/etc/named.rfc1912.zones";
include "/etc/named.root.key";

#qiso.it.zone 正向解析
$TTL 7200
qiso.it.    IN     SOA    qiso.it.    jinrenjie.me.com.    (222 1H 15M 1W 1D)
qiso.it.    IN    NS    dns1.qiso.it.
dns1    IN    A    10.120.1.8
scs        IN    A    10.120.1.88
call    IN    A    10.120.1.6
exsi    IN    A    10.120.1.100
www        IN    CNAME    eip.qiso.it.
eip        IN    A    10.120.1.80
nfs        IN    A    10.120.9.250

#120.10.zone 反向解析
@        IN        SOA    120.10.in-addr.arpa.    jinrenjie.me.com.    (2016091800 1H 15M 1W 1D)
@        IN        NS    dns1.qiso.it.
1.8     IN      PTR     dns1.qiso.it
1.6        IN        PTR        call.qiso.it.
1.88    IN        PTR        csc.qiso.it.
1.100    IN        PTR        exsi.qiso.it.
1.80    IN        PTR        eip.qiso.it.
9.250    IN        PTR        nfs.qiso.it.

配置文件贴上来就乱了，下面是截图：