ntpdate 同步时间错误no server suitable for synchronization found
在一台centos最小化安装的机器上面，yum -y install ntpdate安装ntpdate同步时间。然而执行ntpdate -u ntp.sjtu.edu.cn的时候，死活调不了时间。并报以下错误
|
1 |
30 Oct 23:30:56 ntpdate[8200]: no server suitable for synchronization found |
执行：ntpdate -d ntp.sjtu.edu.cn 命令调试的时候，出现一下信息：
|
1 2 3 4 5 6 7 8 9 10 11 12 |
30 Oct 23:26:54 ntpdate[8183]: ntpdate 4.2.6p5@1.2349-o Sat Nov 23 18:21:48 UTC 2013 (1) Looking for host ntp.sjtu.edu.cn and service ntp host found : 202.120.2.100 transmit(202.120.2.100) transmit(202.120.2.100) transmit(202.120.2.100) transmit(202.120.2.100) transmit(202.120.2.100) 202.120.2.100: Server dropped: no data “......以下信息略” 30 Oct 23:27:33 ntpdate[8183]: no server suitable for synchronization found |
百度了几遍，搜出来的东西都一个样子的，复制来复制去。根本解决不了我的问题。无意中解决了这个问题。分享一下，供大家参考。
在外网另外一台机器上面，同步时间正常，执行的ntpdate -d ntp.sjtu.edu.cn调试，输出以下调试信息
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 |
17 Dec 00:17:19 ntpdate[26682]: ntpdate 4.2.6p5@1.2349-o Tue May 31 10:09:22 UTC 2016 (1) Looking for host cn.ntp.org.cn and service ntp host found : time5.aliyun.com transmit(182.92.12.11) receive(182.92.12.11) transmit(182.92.12.11) receive(182.92.12.11) transmit(182.92.12.11) receive(182.92.12.11) transmit(182.92.12.11) receive(182.92.12.11) server 182.92.12.11, port 123 stratum 2, precision -24, leap 00, trust 000 refid [182.92.12.11], delay 0.06557, dispersion 0.00020 transmitted 4, in filter 4 reference time: dbfe91f0.e0ab0269 Sat, Dec 17 2016 0:16:48.877 originate timestamp: dbfe920f.cce69aec Sat, Dec 17 2016 0:17:19.800 transmit timestamp: dbfe920f.c9ccaaf5 Sat, Dec 17 2016 0:17:19.788 filter delay: 0.06631 0.06557 0.06557 0.06583 0.00000 0.00000 0.00000 0.00000 filter offset: -0.00835 -0.00782 -0.00800 -0.00801 0.000000 0.000000 0.000000 0.000000 delay 0.06557, dispersion 0.00020 offset -0.007821 17 Dec 00:17:19 ntpdate[26682]: adjust time server 182.92.12.11 offset -0.007821 sec |
发现同样的ntp.sjtu.edu.cn域名，解析出来的IP居然不一样！！！！
然后在同步时间有问题的那台机器上面这样执行：
|
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 |
ntpdate -d 182.92.12.11 17 Dec 00:22:12 ntpdate[4876]: ntpdate 4.2.6p5@1.2349-o Mon Nov 14 18:25:09 UTC 2016 (1) Looking for host 182.92.12.11 and service ntp host found : time5.aliyun.com ^[[C^[[Atransmit(182.92.12.11) receive(182.92.12.11) transmit(182.92.12.11) receive(182.92.12.11) transmit(182.92.12.11) receive(182.92.12.11) transmit(182.92.12.11) receive(182.92.12.11) server 182.92.12.11, port 123 stratum 2, precision -24, leap 00, trust 000 refid [182.92.12.11], delay 0.11998, dispersion 0.02696 transmitted 4, in filter 4 reference time: dbfe9340.e0a6e895 Sat, Dec 17 2016 0:22:24.877 originate timestamp: dbfe9341.f1042a0c Sat, Dec 17 2016 0:22:25.941 transmit timestamp: dbfe933a.876de705 Sat, Dec 17 2016 0:22:18.529 filter delay: 0.11998 0.28513 0.22147 0.13644 0.00000 0.00000 0.00000 0.00000 filter offset: 7.335746 7.322472 7.394457 7.357022 0.000000 0.000000 0.000000 0.000000 delay 0.11998, dispersion 0.02696 offset 7.335746 17 Dec 00:22:18 ntpdate[4876]: step time server 182.92.12.11 offset 7.335746 sec |
奇迹出现了，居然同步到时间了！不知道为什么会解析到那个IP上面，不知道是dns解析到错误的IP，还是那个IP不能同步时间。反正就是换个IP就能解决。
作者：昜羊
