NTP服务器-从本地系统时钟同步

Question

我需要创建设备(目前基于Raspberry Pi 3)，它声明为NTP服务器，它与Internet没有连接，NTP应该从本地系统时钟读取实际时间(此时钟是从应用程序设置的)。我的/etc/ntp.conf是：

restrict default kod nomodify notrap nopeer noquery
restrict -6 default kod nomodify notrap nopeer noquery

restrict 127.0.0.1
restrict -6 ::1
restrict ::1

server  127.127.1.0 # local clock
fudge   127.127.1.0 stratum 1

driftfile /var/lib/ntp/ntp.drift
logfile /var/log/ntp.log

当使用service ntp restart命令测试连接(在ntpdate -du localhost之后)时，我得到以下输出：

transmit(::1)
receive(::1)
transmit(127.0.0.1)
receive(127.0.0.1)
transmit(::1)
receive(::1)
transmit(127.0.0.1)
receive(127.0.0.1)
transmit(::1)
receive(::1)
transmit(127.0.0.1)
receive(127.0.0.1)
transmit(::1)
receive(::1)
transmit(127.0.0.1)
receive(127.0.0.1)
::1: Server dropped: strata too high
127.0.0.1: Server dropped: strata too high
server ::1, port 123
stratum 16, precision -20, leap 11, trust 000
refid [::1], delay 0.02573, dispersion 0.00000
transmitted 4, in filter 4
reference time:    00000000.00000000  Thu, Feb  7 2036  6:28:16.000
originate timestamp: ddbf0da9.473a860b  Tue, Nov 21 2017 20:40:09.278
transmit timestamp:  ddbf0da9.47320583  Tue, Nov 21 2017 20:40:09.278
filter delay:  0.02579  0.02573  0.02574  0.02573
         0.00000  0.00000  0.00000  0.00000
filter offset: 0.000018 -0.00001 -0.00000 -0.00001
         0.000000 0.000000 0.000000 0.000000
delay 0.02573, dispersion 0.00000
offset -0.000011

server 127.0.0.1, port 123
stratum 16, precision -20, leap 11, trust 000
refid [127.0.0.1], delay 0.02570, dispersion 0.00000
transmitted 4, in filter 4
reference time:    00000000.00000000  Thu, Feb  7 2036  6:28:16.000
originate timestamp: ddbf0da9.7a812105  Tue, Nov 21 2017 20:40:09.478
transmit timestamp:  ddbf0da9.7a7990a1  Tue, Nov 21 2017 20:40:09.478
filter delay:  0.02571  0.02570  0.02570  0.02570
         0.00000  0.00000  0.00000  0.00000
filter offset: -0.00000 -0.00001 -0.00001 -0.00001
         0.000000 0.000000 0.000000 0.000000
delay 0.02570, dispersion 0.00000
offset -0.000013

21 Nov 20:40:09 ntpdate[1181]: no server suitable for synchronization found

我做错了什么？为什么ntp不能从系统时钟中获得时间？

Answer 1

由于server语句不包括iburst关键字，因此ntpd在重新启动时可能需要几分钟与timesource同步。在此期间，它提供给其他服务器的答案被认为是不可靠的。

是的，即使它能有效地与自己同步。

在ntpdate -d输出中，stratum 16, precision -20, leap 11意味着ntpd认为“我现在还没有准备好为其他人提供时间服务。”