我已经在chroot设置了named ，并且它已经工作了一些日子。 现在它没有find某个域的IP：
# dig arstechnica.com ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.30.rc1.el6_6.1 <<>> arstechnica.com ;; global options: +cmd ;; connection timed out; no servers could be reached
其他域通常被发现：
# dig serverfault.com ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.30.rc1.el6_6.1 <<>> serverfault.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 27016 ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2 ;; QUESTION SECTION: ;serverfault.com. IN A ;; ANSWER SECTION: serverfault.com. 98 IN A 198.252.206.140 ;; AUTHORITY SECTION: serverfault.com. 172598 IN NS cf-dns02.serverfault.com. serverfault.com. 172598 IN NS cf-dns01.serverfault.com. ;; ADDITIONAL SECTION: cf-dns02.serverfault.com. 172598 IN A 173.245.59.4 cf-dns01.serverfault.com. 172598 IN A 173.245.58.53 ;; Query time: 0 msec ;; SERVER: 127.0.0.1#53(127.0.0.1) ;; WHEN: Mon Dec 22 11:06:10 2014 ;; MSG SIZE rcvd: 127
named.conf ：
# cat /var/named/chroot/var/named/chroot/etc/named.conf options { listen-on port 53 { 127.0.0.1; }; listen-on-v6 port 53 { ::1; }; 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 { localhost; }; recursion yes; dnssec-enable yes; dnssec-validation yes; dnssec-lookaside auto; /* Path to ISC DLV key */ bindkeys-file "/etc/named.iscdlv.key"; managed-keys-directory "/var/named/dynamic"; }; logging { channel default_debug { file "data/named.run"; severity dynamic; }; }; zone "." IN { type hint; file "named.ca"; }; include "/etc/named.rfc1912.zones"; include "/etc/named.root.key";
该目录中的所有文件：
# ll /var/named/chroot/var/named/chroot/etc/ total 16 -rw-r--r--. 1 root root 118 Jul 21 2011 localtime drwxr-x---. 2 root named 4096 Dec 12 02:25 named -rw-r-----. 1 root named 1008 Dec 17 20:02 named.conf -rw-r--r--. 1 root root 0 Dec 22 10:35 named.iscdlv.key -rw-r--r--. 1 root root 0 Dec 22 10:35 named.rfc1912.zones -rw-r--r--. 1 root root 0 Dec 22 10:35 named.root.key drwxr-x---. 3 root named 4096 Dec 17 19:15 pki -rw-r--r--. 1 root root 0 Dec 22 10:35 rndc.key
我错过了什么？
+trace添加：
# dig arstechnica.com +trace ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.30.rc1.el6_6.1 <<>> arstechnica.com +trace ;; global options: +cmd . 516879 IN NS m.root-servers.net. . 516879 IN NS h.root-servers.net. . 516879 IN NS g.root-servers.net. . 516879 IN NS j.root-servers.net. . 516879 IN NS a.root-servers.net. . 516879 IN NS l.root-servers.net. . 516879 IN NS e.root-servers.net. . 516879 IN NS f.root-servers.net. . 516879 IN NS k.root-servers.net. . 516879 IN NS b.root-servers.net. . 516879 IN NS d.root-servers.net. . 516879 IN NS i.root-servers.net. . 516879 IN NS c.root-servers.net. ;; Received 228 bytes from 127.0.0.1#53(127.0.0.1) in 577 ms com. 172800 IN NS m.gtld-servers.net. com. 172800 IN NS l.gtld-servers.net. com. 172800 IN NS k.gtld-servers.net. com. 172800 IN NS j.gtld-servers.net. com. 172800 IN NS i.gtld-servers.net. com. 172800 IN NS h.gtld-servers.net. com. 172800 IN NS g.gtld-servers.net. com. 172800 IN NS f.gtld-servers.net. com. 172800 IN NS e.gtld-servers.net. com. 172800 IN NS d.gtld-servers.net. com. 172800 IN NS c.gtld-servers.net. com. 172800 IN NS b.gtld-servers.net. com. 172800 IN NS a.gtld-servers.net. ;; Received 493 bytes from 192.58.128.30#53(192.58.128.30) in 2270 ms arstechnica.com. 172800 IN NS ns1.servercentral.net. arstechnica.com. 172800 IN NS ns2.servercentral.net. ;; Received 118 bytes from 192.12.94.30#53(192.12.94.30) in 579 ms ;; connection timed out; no servers could be reached
挖到github：
# dig github.com +trace ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.30.rc1.el6_6.1 <<>> github.com +trace ;; global options: +cmd . 516495 IN NS k.root-servers.net. . 516495 IN NS e.root-servers.net. . 516495 IN NS f.root-servers.net. . 516495 IN NS b.root-servers.net. . 516495 IN NS g.root-servers.net. . 516495 IN NS d.root-servers.net. . 516495 IN NS m.root-servers.net. . 516495 IN NS c.root-servers.net. . 516495 IN NS j.root-servers.net. . 516495 IN NS h.root-servers.net. . 516495 IN NS a.root-servers.net. . 516495 IN NS i.root-servers.net. . 516495 IN NS l.root-servers.net. ;; Received 508 bytes from 127.0.0.1#53(127.0.0.1) in 5 ms com. 172800 IN NS a.gtld-servers.net. com. 172800 IN NS b.gtld-servers.net. com. 172800 IN NS c.gtld-servers.net. com. 172800 IN NS d.gtld-servers.net. com. 172800 IN NS e.gtld-servers.net. com. 172800 IN NS f.gtld-servers.net. com. 172800 IN NS g.gtld-servers.net. com. 172800 IN NS h.gtld-servers.net. com. 172800 IN NS i.gtld-servers.net. com. 172800 IN NS j.gtld-servers.net. com. 172800 IN NS k.gtld-servers.net. com. 172800 IN NS l.gtld-servers.net. com. 172800 IN NS m.gtld-servers.net. ;; Received 488 bytes from 193.0.14.129#53(193.0.14.129) in 74 ms github.com. 172800 IN NS ns1.p16.dynect.net. github.com. 172800 IN NS ns3.p16.dynect.net. github.com. 172800 IN NS ns2.p16.dynect.net. github.com. 172800 IN NS ns4.p16.dynect.net. ;; Received 178 bytes from 192.31.80.30#53(192.31.80.30) in 323 ms github.com. 30 IN A 192.30.252.131 github.com. 86400 IN NS ns4.p16.dynect.net. github.com. 86400 IN NS ns2.p16.dynect.net. github.com. 86400 IN NS ns1.p16.dynect.net. github.com. 86400 IN NS ns3.p16.dynect.net. ;; Received 130 bytes from 204.13.251.16#53(204.13.251.16) in 10 ms
在服务器使用的IP地址（ 64.xxx ）上设置的networking掩码是255.0.0.0 ，这是广泛的，这意味着对任何也以IP地址64.开头的域的请求不被路由出服务器正确。
解决此问题的方法是将本地计算机上的IP地址上使用的networking掩码降低为255.255.255.0，这意味着从64.开始的任何地址仍将从外部parsing到本机。