前几天我在我的networking上进行了ntp安装，一切运行良好。 一个节点被设置为与上游服务器同步，而另一个节点被设置为上游同步。
昨天我从CentOS 6.4 – > 6.5更新，现在所有的ntpfunction已经停止了预期的运行。
在尝试debugging情况下，我在上游服务器上运行以下内容：
$ -> ntpq -pnd ::1: timed out, nothing received ***Request timed out $ -> ntpq -4 -pnd 1 packets reassembled into response remote refid st t when poll reach delay offset jitter ============================================================================== 2 packets reassembled into response *50.116.55.65 64.246.132.14 2 u 42 64 37 77.742 189.392 14.812 2 packets reassembled into response 199.102.46.73 .GPS. 1 u 44 64 37 73.786 216.082 18.406 2 packets reassembled into response 198.60.22.240 .GPS. 1 u 48 64 37 22.617 189.405 15.996 2 packets reassembled into response 127.127.1.0 .LOCL. 10 l 306 64 20 0.000 0.000 0.000 我在节点上得到了相同的结果（保存为差异IP）。 看来，ntp服务默认是ipv6，我没有configuration。 我读过一些网站说传递-4到ntpd服务，但我怎么做，使用chkconfig？ 其他一些读数表明，我应该通过内核禁用ipv6，但这似乎是矫枉过正。
有什么build议么？
为了完整性，添加configuration文件：
driftfile /var/lib/ntp/drift # Permit time synchronization with our time source, but do not # permit the source to query or modify the service on this system. restrict default kod nomodify notrap nopeer noquery restrict -6 default kod nomodify notrap nopeer noquery # Permit all access over the loopback interface. This could # be tightened as well, but to do so would effect some of # the administrative functions. restrict 127.0.0.1 restrict 10.0.0.0 mask 255.255.192.0 nomodify notrap server 0.centos.pool.ntp.org iburst server 1.centos.pool.ntp.org server 2.centos.pool.ntp.org # In case net access is temporarily down server 127.127.1.0 fudge 127.127.1.0 stratum 10
由于它试图使用IPv6，你可能想要在你的configuration文件中允许它：
restrict -6 ::1