对于host 正反查询提示出错 Host xxx not found: 3(NXDOMAIN)的解决方法

 host 正反查询时候总是提示出错

root@mail:~# host mail.rhel5.com

Host mail.rhel5.com not found: 3(NXDOMAIN)

root@mail:~# host 192.168.56.101

Host 101.56.168.192.in-addr.arpa. not found: 3(NXDOMAIN)

 

查看日志 cat  /var/log/messages

 

Mar 22 20:49:51 server named[11421]: found 1 CPU, using 1 worker thread

Mar 22 20:49:51 server named[11421]: using up to 4096 sockets

Mar 22 20:49:51 server named[11421]: loading configuration from '/etc/named.c

'

Mar 22 20:49:51 server named[11421]: using default UDP/IPv4 port range: [1024

5535]

Mar 22 20:49:51 server named[11421]: using default UDP/IPv6 port range: [1024

5535]

Mar 22 20:49:51 server named[11421]: listening on IPv4 interface eth0, 192.16

6.101#53

Mar 22 20:49:51 server named[11421]: command channel listening on 127.0.0.1#9

Mar 22 20:49:51 server named[11421]: command channel listening on ::1#953

Mar 22 20:49:51 server named[11421]: the working directory is not writable

Mar 22 20:49:51 server named[11421]: zone 56.168.192.in-addr.arpa/IN: loaded

ial 20120322

Mar 22 20:49:51 server named[11421]: zone rhel5.com/IN: loaded serial 2012032

Mar 22 20:49:51 server named[11421]: running

 

同时也检查

/var/named/chroot/var/named/rhel5.com.zone

/var/named/chroot/var/named/56.168.192.in-addr.arpa.zone

没发现错误   。使用 named-checkzone有时候也检查不出来错误。

   

问题出在这里 the working directory is not writable

解决办法：

后来先关闭防火墙，不然设置布尔值修正SElinux环境会提示无权限的 root@mail:~# getsebool -a | grep named

named_disable_trans --> off

named_write_master_zones -->off

 

setsebool -P named_write_master_zones on

 

root@mail:~# getsebool -a | grep named

named_disable_trans --> off

named_write_master_zones --> on

 

再检查日志没发现报错

Mar 23 04:18:41 mail named[6024]: found 1 CPU, using 1 worker thread

Mar 23 04:18:41 mail named[6024]: using up to 4096 sockets

Mar 23 04:18:41 mail named[6024]: loading configuration from '/etc/named.conf

'

Mar 23 04:18:41 mail named[6024]: using default UDP/IPv4 port range: [1024, 6

5535]

Mar 23 04:18:41 mail named[6024]: using default UDP/IPv6 port range: [1024, 6

5535]

Mar 23 04:18:41 mail named[6024]: listening on IPv4 interface eth0, 192.168.5

6.101#53

Mar 23 04:18:41 mail named[6024]: command channel listening on 127.0.0.1#953

Mar 23 04:18:41 mail named[6024]: command channel listening on ::1#953

Mar 23 04:18:41 mail named[6024]: zone 56.168.192.in-addr.arpa/IN: loaded ser

ial 20120322

Mar 23 04:18:41 mail named[6024]: zone rhel5.com/IN: loaded serial 20120322

Mar 23 04:18:41 mail named[6024]: running

 

named的工作目录不可写解决了。但是host 正反查询还是 not found: 3(NXDOMAIN)

 

BIND是SElinux使用目标策略限制的服务之一。

估计是不正确的SElinux环境从以前的位置携带过来。

使用 restorecon -R / var/named/chroot.

但是新的问题出现了 /var/named/ 下的正、反解和 /var/named/chroot.的不同。

 

/var/named/chroot/var/named/localhost.zone 的内容代替了原来的/var/named/chroot/var/named/rhel5.com.zone 

 

这里贴出的是/v ar/named 和/var/named/chroot/var/named/rhel5.com.zone

 root@mail:~# cat /v ar/named /chroot /var/named/rhel5.com.zone
$TTL    86400
@               IN SOA  @       root (
42              ; serial (d. adams)
3H              ; refresh
15M             ; retry
1W              ; expiry
1D )            ; minimum

IN NS           @
IN A            127.0.0.1
IN AAAA         ::1

root@mail:~# cat  /var/named/rhel5.com.zone
$TTL    86400
@               IN SOA mail.rhel5.com.          root.rhel5.com. (
20120322        ; serial (d.adams)
3H              ; refresh
15M             ; retry
1W              ; expiry
1D )            ; minimum

@               IN NS           mail.rhel5.com.
mail            IN A            192.168.56.101
@               IN MX   5       mail.rhel5.com.
mail            IN A            192.168.56.101
www             IN A            192.168.56.123
rhel5.com.      IN A            192.168.56.101

 

这个问题应该是

分别cat /var/named/下的正解和反解文件到/var/named/chroot/var/named/然后重启 。

cat /var/named/rhel5.com.zone > var/named/chroot/var/named/rhel5.com.zone

cat /var/named/56.168.192.in-addr.arpa.zone > /var/named/chroot/var/named/56.168.192.in-addr.arpa.zone

 

最后重启named服务 service named restart

host 正反查询总算是正常了。

root@mail:~# host 192.168.56.101

101.56.168.192.in-addr.arpa domain name pointer mail.rhel5.com.

root@mail:~# host mail.rhel5.com

mail.rhel5.com has address 192.168.56.101

 

 

后记，在网上谷歌和百度都找了关于 Host xxx  not found: 3(NXDOMAIN) 

不管是中文的还是英文都看了，而且不对症，治不了这Host正反解析报错问题。

参照红帽官方教材RH253访问控制：BIND中SElinux的布尔值和SElinux环境介绍。