Невозможно определить ошибку главного DNS-сервера:

Я пытаюсь использовать передачу зоны между моим главным и подчиненным DNS-серверами, однако я не могу запустить именованную службу и получаю следующую ошибку:

[root@balsam named]# systemctl status named.service
● named.service - Berkeley Internet Name Domain (DNS)
   Loaded: loaded (/usr/lib/systemd/system/named.service; enabled; vendor preset: disabled)
   Active: failed (Result: exit-code) since Sat 2017-03-11 14:43:58 EST; 7s ago
  Process: 2510 ExecStop=/bin/sh -c /usr/sbin/rndc stop > /dev/null 2>&1 || /bin/kill -TERM $MAINPID (code=exited, status=0/SUCCESS)
  Process: 2440 ExecStart=/usr/sbin/named -u named $OPTIONS (code=exited, status=0/SUCCESS)
  Process: 2550 ExecStartPre=/bin/bash -c if [ ! "$DISABLE_ZONE_CHECKING" == "yes" ]; then /usr/sbin/named-checkconf -z /etc/named.conf; else echo "Checking of zone files is disabled"; fi (code=exited, status=1/FAILURE)
 Main PID: 2443 (code=exited, status=0/SUCCESS)

Mar 11 14:43:58 balsam.coniferous.trees.ops bash[2550]: dns_rdata_fromtext: mydb-for-172.30.20:16: near 'pine.coniferous.trees.ops.': not a valid number
Mar 11 14:43:58 balsam.coniferous.trees.ops bash[2550]: zone 20.30.172.in-addr.arpa/IN: loading from master file mydb-for-172.30.20 failed: not a valid number
Mar 11 14:43:58 balsam.coniferous.trees.ops bash[2550]: zone 20.30.172.in-addr.arpa/IN: not loaded due to errors.
Mar 11 14:43:58 balsam.coniferous.trees.ops bash[2550]: _default/20.30.172.in-addr.arpa./IN: not a valid number
Mar 11 14:43:58 balsam.coniferous.trees.ops bash[2550]: zone ajfoncec.org/IN: loaded serial 2016010301
Mar 11 14:43:58 balsam.coniferous.trees.ops bash[2550]: zone 62.168.192.in-addr.arpa/IN: loaded serial 2016010301
Mar 11 14:43:58 balsam.coniferous.trees.ops systemd[1]: named.service: control process exited, code=exited status=1
Mar 11 14:43:58 balsam.coniferous.trees.ops systemd[1]: Failed to start Berkeley Internet Name Domain (DNS).
Mar 11 14:43:58 balsam.coniferous.trees.ops systemd[1]: Unit named.service entered failed state.
Mar 11 14:43:58 balsam.coniferous.trees.ops systemd[1]: named.service failed.

Что это означает? Кажется, я не могу это понять.

Вот файлы зоны, в которых упоминается:

mydb-for-172.30.20

$TTL    3D
@       IN      SOA     balsam.coniferous.trees.ops.      pine.coniferous.trees.ops.(
                2016010301       ; Serial
                8H      ; Refresh
                2H      ; Retry
                1W      ; Expire
                1D      ; Negative Cache TTL
);
@           IN      NS      balsam.coniferous.trees.ops.
1           IN  PTR larch.coniferous.trees.ops.
2           IN      PTR     balsam.coniferous.trees.ops.
3                       IN      PTR     spruce.coniferous.trees.ops.
5                       IN      PTR     pine.coniferous.trees.ops.
6                       IN      PTR     fir.coniferous.trees.ops.
8                       IN      PTR     bristlecone.coniferous.trees.ops.
5           IN  MX  pine.coniferous.trees.ops.

и еще один mydb-for-ajfoncec-org

$TTL    3D
@       IN      SOA     vm1.ajfoncec.org.      hostmaster.ajfoncec.org.(
                2016010301       ; Serial
                8H      ; Refresh
                2H      ; Retry
                1W      ; Expire
                1D      ; Negative Cache TTL
);
@       IN      NS      vm1.ajfoncec.org.
vm1     IN      A       192.168.62.2
vm2     IN      A       192.168.62.3
vm3     IN      A       192.168.62.4
host    IN      A       192.168.62.1

ой и mydb-for-coniferous-trees-ops

$TTL    3D
@       IN      SOA     balsam.coniferous.trees.ops.      pine.coniferous.trees.ops.(
                2016010301       ; Serial
                8H      ; Refresh
                2H      ; Retry
                1W      ; Expire
                1D      ; Negative Cache TTL
);
@       IN      NS      balsam.coniferous.trees.ops.
balsam  IN      A       172.30.20.2
spruce  IN  A   172.30.20.3
pine    IN  A   172.30.20.5
fir IN  A   172.30.20.6
bristlecone IN  A   172.30.20.8
larch   IN  A   172.30.20.1
pine    IN  MX  0   172.30.20.5