问题[systemd-timesyncd](server)

在我的 yocto 发行版中启用了该服务systemd-timesyncd.service。其配置文件（timesyncd.conf）如下：

#  This file is part of systemd.
#
#  systemd is free software; you can redistribute it and/or modify it
#  under the terms of the GNU Lesser General Public License as published by
#  the Free Software Foundation; either version 2.1 of the License, or
#  (at your option) any later version.
#
# Entries in this file show the compile time defaults.
# You can change settings by editing this file.
# Defaults can be restored by simply deleting this file.
#
# See timesyncd.conf(5) for details.

[Time]
#NTP=
#FallbackNTP=time1.google.com time2.google.com time3.google.com time4.google.com
#RootDistanceMaxSec=5
#PollIntervalMinSec=32
#PollIntervalMaxSec=2048

如您所见，NTP未设置配置文件的选项。尽管如此，服务设置了系统日期，并且通过一些登录journalctl，我看到 NTP 服务器可能是time1.google.com.

我的问题是：NTP 服务器在哪里设置systemd-timesyncd？

谢谢

我正在尝试调试一些网络连接问题，我看到：

systemd-timesyncd: Network configuration changed, trying to establish connection.

在系统日志中。我试图用谷歌搜索它，但我找不到一个好的定义。这是我需要担心的事情吗？配置更改是否仅在 的上下文中timesyncd？谢谢。

我正在尝试为 Ubuntu 服务器配置某种时间同步。服务器位于云提供商无状态防火墙后面。通过反复试验，我发现为了ntp工作，我必须打开传入的 UDP 端口 123。

然后我读到systemd-timesyncd现在首选使用，所以我尝试切换到那个。但这没有用。服务日志充满了

systemd-timesyncd[2656121]: Timed out waiting for reply from 91.189.89.199:123 (ntp.ubuntu.com).
systemd-timesyncd[2656121]: Timed out waiting for reply from 91.189.94.4:123 (ntp.ubuntu.com).

只有在我也将防火墙中的临时 UDP 端口列入白名单之后，32768–65535这才开始起作用：

systemd-timesyncd[2656121]: Initial synchronization to time server 91.189.91.157:123 (ntp.ubuntu.com).

是否真的需要打开该范围的端口才能运行systemd-timesync？

编辑以回应@Jesus-Loves-You 在下面的回复。更高的端口应该不是必需的，但在我的情况下，出于某种原因，它们显然是必需的。查看服务日志systemd-timesync（由我用 注释#）：

# Before I enabled the 32786+ ports
May 21 11:49:21 myhost systemd-timesyncd[2656121]: Timed out waiting for reply from 91.189.89.198:123 (ntp.ubuntu.com).

# After I enabled the ports
May 21 11:49:06 myhost systemd-timesyncd[2656121]: Initial synchronization to time server 91.189.91.157:123 (ntp.ubuntu.com).

# After I disabled them again. Note that there are no log entries inbetween for almost
# three days. This, imo, pretty much proves that the ports are required.
May 24 09:29:34 myhost systemd-timesyncd[2656121]: Timed out waiting for reply from 91.189.91.157:123 (ntp.ubuntu.com).

有关港口的更多信息：

root@host:/# netstat -ulpvn | grep systemd
udp        0      0 127.0.0.53:53           0.0.0.0:*                           2218041/systemd-res
udp        0      0 0.0.0.0:42212           0.0.0.0:*                           2656121/systemd-tim

看起来42212是服务期望通信发生的端口。但几分钟后，当下一次轮询发生时：

root@host:/# netstat -ulpvn | grep systemd
udp        0      0 127.0.0.53:53           0.0.0.0:*                           2218041/systemd-res
udp        0      0 0.0.0.0:37240           0.0.0.0:*                           2656121/systemd-tim

现在端口变了。几分钟后，它再次变为51120。因此，我得出结论，该服务每次尝试同步时都会尝试在随机端口上进行通信。

我在我的 KVM 主机（Lubuntu 20.04）上遇到了一些崩溃问题，在进行故障排除时，我注意到了一些与时间相关的错误。

经过进一步调查，令我惊恐的是，我发现时间没有同步。我确定它是以前设置的，我不知道它是如何变为未设置的。

admin@virtland:~$ sudo timedatectl
[sudo] password for admin: 
               Local time: Fri 2020-07-10 09:14:14 EDT  
           Universal time: Fri 2020-07-10 13:14:14 UTC  
                 RTC time: Fri 2020-07-10 13:14:14      
                Time zone: America/New_York (EDT, -0400)
System clock synchronized: no                           
              NTP service: n/a                          
          RTC in local TZ: no                           
admin@virtland:~$ 

我找到了这个线程并尝试了最佳答案，但无济于事。 https://askubuntu.com/questions/929805/timedatectl-ntp-sync-cannot-set-to-yes

admin@virtland:~$ sudo systemctl stop ntp
admin@virtland:~$ sudo ntpd -gq
10 Jul 09:17:57 ntpd[34358]: ntpd [email protected] (1): Starting
10 Jul 09:17:57 ntpd[34358]: Command line: ntpd -gq
10 Jul 09:17:57 ntpd[34358]: proto: precision = 0.070 usec (-24)
10 Jul 09:17:57 ntpd[34358]: leapsecond file ('/usr/share/zoneinfo/leap-seconds.list'): good hash signature
10 Jul 09:17:57 ntpd[34358]: leapsecond file ('/usr/share/zoneinfo/leap-seconds.list'): loaded, expire=2020-12-28T00:00:00Z last=2017-01-01T00:00:00Z ofs=37
10 Jul 09:17:57 ntpd[34358]: Listen and drop on 0 v6wildcard [::]:123
10 Jul 09:17:57 ntpd[34358]: Listen and drop on 1 v4wildcard 0.0.0.0:123
10 Jul 09:17:57 ntpd[34358]: Listen normally on 2 lo 127.0.0.1:123
10 Jul 09:17:57 ntpd[34358]: Listen normally on 3 enp6s0 10.0.0.18:123
10 Jul 09:17:57 ntpd[34358]: Listen normally on 4 lo [::1]:123
10 Jul 09:17:57 ntpd[34358]: Listen normally on 5 enp6s0 [fe80::7285:c2ff:fe65:9f19%3]:123
10 Jul 09:17:57 ntpd[34358]: Listening on routing socket on fd #22 for interface updates
10 Jul 09:17:58 ntpd[34358]: Soliciting pool server 209.50.63.74
10 Jul 09:17:59 ntpd[34358]: Soliciting pool server 4.53.160.75
10 Jul 09:18:00 ntpd[34358]: Soliciting pool server 69.89.207.199
10 Jul 09:18:00 ntpd[34358]: Soliciting pool server 72.30.35.88
10 Jul 09:18:01 ntpd[34358]: Soliciting pool server 173.0.48.220
10 Jul 09:18:01 ntpd[34358]: Soliciting pool server 162.159.200.1
10 Jul 09:18:01 ntpd[34358]: Soliciting pool server 108.61.73.243
10 Jul 09:18:02 ntpd[34358]: Soliciting pool server 208.79.89.249
10 Jul 09:18:02 ntpd[34358]: Soliciting pool server 208.67.75.242
10 Jul 09:18:02 ntpd[34358]: Soliciting pool server 91.189.94.4
10 Jul 09:18:03 ntpd[34358]: Soliciting pool server 91.189.89.198
10 Jul 09:18:03 ntpd[34358]: Soliciting pool server 67.217.112.181
10 Jul 09:18:04 ntpd[34358]: Soliciting pool server 91.189.89.199
10 Jul 09:18:04 ntpd[34358]: Soliciting pool server 64.225.34.103             
10 Jul 09:18:05 ntpd[34358]: Soliciting pool server 91.189.91.157             
10 Jul 09:18:06 ntpd[34358]: Soliciting pool server 2001:67c:1560:8003::c8    
10 Jul 09:18:06 ntpd[34358]: ntpd: time slew +0.001834 s                      
ntpd: time slew +0.001834s                                                    
admin@virtland:~$ sudo service ntp start                                       
admin@virtland:~$ sudo timedatectl                             
               Local time: Fri 2020-07-10 09:18:21 EDT                        
           Universal time: Fri 2020-07-10 13:18:21 UTC                        
                 RTC time: Fri 2020-07-10 13:18:21                            
                Time zone: America/New_York (EDT, -0400)                      
System clock synchronized: no                                                 
              NTP service: n/a                                                
          RTC in local TZ: no                                                 
admin@virtland:~$                  

我想也许我需要使用一些最新的指令，所以我尝试了这个： https ://linuxconfig.org/how-to-sync-time-on-ubuntu-20-04-focal-fossa-linux

admin@virtland:~$ timedatectl set-ntp off
Failed to set ntp: NTP not supported                                          
admin@virtland:~$ timedatectl set-ntp on
Failed to set ntp: NTP not supported                                          

然后我从另一个线程尝试了这个：

admin@virtland:~$ sudo systemctl status systemd-timesyncd.service
[sudo] password for admin: 
● systemd-timesyncd.service
     Loaded: masked (Reason: Unit systemd-timesyncd.service is masked.)
     Active: inactive (dead)

我从未接触过 timesyncd.conf，但无论如何它都被完全注释掉了：

cat /etc/systemd/timesyncd.conf                         
#  This file is part of systemd.                                              
#                                                                             
#  systemd is free software; you can redistribute it and/or modify it         
#  under the terms of the GNU Lesser General Public License as published by   
#  the Free Software Foundation; either version 2.1 of the License, or        
#  (at your option) any later version.                                        
#                                                                             
# Entries in this file show the compile time defaults.                        
# You can change settings by editing this file.                               
# Defaults can be restored by simply deleting this file.                      
#                                                                             
# See timesyncd.conf(5) for details.                                          
                                                                              
[Time]                                                                        
#NTP=                                                                         
#FallbackNTP=ntp.ubuntu.com                                                   
#RootDistanceMaxSec=5                                                         
#PollIntervalMinSec=32                                                        
#PollIntervalMaxSec=2048 

我再次检查了 timedatectl，现在它打开了，但仍然没有使用 NTP。我知道 NTP 更精确，这在某些情况下可能很重要。不确定带有 pci 直通的虚拟化是否需要非常精确的时间。

从我正在阅读的其他内容中，我认为 NTP 可能与 timesyncd 冲突。所以暂时去掉ntp：

sudo systemctl stop ntp
sudo apt-get purge ntp

但在清除 ntp 后，NTP 显示为活动状态！

admin@virtland:~$ timedatectl
               Local time: Fri 2020-07-10 09:34:52 EDT  
           Universal time: Fri 2020-07-10 13:34:52 UTC  
                 RTC time: Fri 2020-07-10 13:34:52      
                Time zone: America/New_York (EDT, -0400)
System clock synchronized: yes                          
              NTP service: active                       
          RTC in local TZ: no     

我要疯了吗？NTP 是否还在这里？没有。

admin@virtland:~$ sudo systemctl start ntp
Failed to start ntp.service: Unit ntp.service not found.

很抱歉没有提出更集中的问题，但这里到底发生了什么？

我很好，真的迷路了。另外，我稍后会编辑这篇文章，并就删除 NTP（并因此激活它？！）是否解决了导致我陷入这个兔子洞的稳定性问题做出了一个不回答。

编辑：我做的下一件事是在 timesyncd 上禁用 ntp 并（重新）安装 NTP，如此处所述。https://www.digitalocean.com/community/tutorials/how-to-set-up-time-synchronization-on-ubuntu-18-04

结果是：

admin@virtland:~$ ntpq -p
     remote           refid      st t when poll reach   delay   offset  jitter
==============================================================================
 0.us.pool.ntp.o .POOL.          16 p    -   64    0    0.000    0.000   0.000
 1.us.pool.ntp.o .POOL.          16 p    -   64    0    0.000    0.000   0.000
 2.us.pool.ntp.o .POOL.          16 p    -   64    0    0.000    0.000   0.000
 3.us.pool.ntp.o .POOL.          16 p    -   64    0    0.000    0.000   0.000
 0.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 1.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 2.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 3.ubuntu.pool.n .POOL.          16 p    -   64    0    0.000    0.000   0.000
 ntp.ubuntu.com  .POOL.          16 p    -   64    0    0.000    0.000   0.000
admin@virtland:~$ timedatectl
               Local time: Fri 2020-07-10 10:35:39 EDT  
           Universal time: Fri 2020-07-10 14:35:39 UTC  
                 RTC time: Fri 2020-07-10 14:35:40      
                Time zone: America/New_York (EDT, -0400)
System clock synchronized: no                                                 
              NTP service: n/a                                                
          RTC in local TZ: no                                                 
admin@virtland:~$ systemctl status systemd-timesyncd 
● systemd-timesyncd.service                                                   
     Loaded: masked (Reason: Unit systemd-timesyncd.service is masked.)       
     Active: inactive (dead)                                                  
admin@virtland:~$ nano /etc/ntp.conf
admin@virtland:~$ systemctl status systemd-timesyncd                           
● systemd-timesyncd.service                                                   
     Loaded: masked (Reason: Unit systemd-timesyncd.service is masked.)       
     Active: inactive (dead)                                                  
admin@virtland:~$ ntpstat
unsynchronised                                                                
   polling server every 8 s 

我按照 Michael Hampton 的建议撤销了这些更改：这是否意味着它正在工作？

boss@virtland:~$ sudo systemctl stop ntp
Failed to stop ntp.service: Unit ntp.service not loaded.
boss@virtland:~$ sudo timedatectl set-ntp yes
boss@virtland:~$ sudo timedatectl set-ntp on
boss@virtland:~$ ntpq -p
bash: /usr/bin/ntpq: No such file or directory
boss@virtland:~$ systemctl status systemd-timesyncd 
● systemd-timesyncd.service - Network Time Synchronization
     Loaded: loaded (/lib/systemd/system/systemd-timesyncd.service; enabled; >
     Active: active (running) since Fri 2020-07-10 10:49:18 EDT; 50s ago
       Docs: man:systemd-timesyncd.service(8)
   Main PID: 108365 (systemd-timesyn)
     Status: "Initial synchronization to time server 91.189.94.4:123 (ntp.ubu>
      Tasks: 2 (limit: 154317)
     Memory: 1.8M
     CGroup: /system.slice/systemd-timesyncd.service
             └─108365 /lib/systemd/systemd-timesyncd

Jul 10 10:49:17 virtland systemd[1]: Starting Network Time Synchronization...
Jul 10 10:49:18 virtland systemd[1]: Started Network Time Synchronization.
Jul 10 10:49:18 virtland systemd-timesyncd[108365]: Initial synchronization t>
lines 1-14/14 (END)

 timedatectl
               Local time: Fri 2020-07-10 10:52:56 EDT  
           Universal time: Fri 2020-07-10 14:52:56 UTC  
                 RTC time: Fri 2020-07-10 14:52:56      
                Time zone: America/New_York (EDT, -0400)
System clock synchronized: yes                          
              NTP service: active                       
          RTC in local TZ: no            

所以我想它正在工作。由于让我走上这条道路的崩溃仍在发生，我想时间不是问题。