搭建DNS服务器出现错误，不知道是因为什么

[Landseer_]

[root@bogon etc]# vi named.conf
[root@bogon etc]# /etc/init.d/named restart
Stopping named: [ OK
Starting named:
Error in named configuration:
/etc/named.rfc1912.zones:13: unknown option 'zone'
/etc/named.rfc1912.zones:19: unknown option 'zone'
/etc/named.rfc1912.zones:25: unknown option 'zone'
/etc/named.rfc1912.zones:31: unknown option 'zone'
/etc/named.rfc1912.zones:37: unknown option 'zone'
/etc/named.root.key:1: unknown option 'managed-keys'
[FAILE
[root@bogon etc]# vi named.conf
[root@bogon etc]# /etc/init.d/named restart
Stopping named: [ OK
Starting named:
Error in named configuration:
/etc/named.rfc1912.zones:13: unknown option 'zone'
/etc/named.rfc1912.zones:19: unknown option 'zone'
/etc/named.rfc1912.zones:25: unknown option 'zone'
/etc/named.rfc1912.zones:31: unknown option 'zone'
/etc/named.rfc1912.zones:37: unknown option 'zone'
/etc/named.root.key:1: unknown option 'managed-keys'
[FAILE
[root@bogon etc]# vi named.conf
[root@bogon etc]# /etc/init.d/named restart
Stopping named: [ OK
Starting named: [ OK
[root@bogon etc]#

当我注释掉//include "/etc/named.rfc1912.zones";
//include "/etc/named.root.key";

就能启动了，是什么原理