如何迫使时间同步？

Question

我运行了一个需要及时运行的DB集群。可悲的是，有时我的VM主机会将带有这样的DB节点的VM移动到另一个主机上，而此时却缺少一秒钟或更多的时间。然后我的DB节点关闭并由systemd重新启动。

我的systemd文件包含以下内容：

ExecStartPre=-+/usr/bin/chronyc -a makestep
ExecStart=/usr/local/bin/.......

我期望在这样的时间间隔关闭数据库后立即同步我的时间。但由于我的日志，，它花了长达7分钟的时间，直到区别被识别和修复。我的数据库检测到每次重新启动时的间隙，然后再次关闭。最后，我得到了这个时间日志：

Nov 16 10:25:51 dc3-sirius chronyd[164166]: System clock was stepped by 0.000020 seconds
Nov 16 10:26:07 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:26:23 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:26:39 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:26:55 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:27:11 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:27:27 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:27:43 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:27:59 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:28:15 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:28:31 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:28:47 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:28:59 dc3-sirius chronyd[164166]: Source 81.169.199.94 replaced with 212.71.244.243
Nov 16 10:29:03 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:29:19 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:29:32 dc3-sirius chronyd[164166]: Selected source 109.230.227.90
Nov 16 10:29:35 dc3-sirius chronyd[164166]: System clock was stepped by 0.003850 seconds
Nov 16 10:29:51 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:30:07 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:30:23 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:30:39 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:30:55 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:31:11 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:31:27 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:31:43 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:31:59 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:32:13 dc3-sirius chronyd[164166]: Can't synchronise: no majority
Nov 16 10:32:15 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:32:31 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:32:33 dc3-sirius chronyd[164166]: Selected source 109.230.227.90
Nov 16 10:32:33 dc3-sirius chronyd[164166]: System clock wrong by 1.101260 seconds, adjustment started
Nov 16 10:32:48 dc3-sirius chronyd[164166]: System clock was stepped by 1.003151 seconds
Nov 16 10:33:04 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:33:21 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:33:37 dc3-sirius chronyd[164166]: System clock was stepped by -0.000000 seconds
Nov 16 10:33:51 dc3-sirius chronyd[164166]: Selected source 162.159.200.123
Nov 16 10:33:53 dc3-sirius chronyd[164166]: System clock was stepped by 0.409613 seconds

如您所见，它在>7分钟后开始同步时钟：

我的数据库在10点25分51分发现了这个问题。由此，在每次重新启动数据库之前，执行上述命令几次，以重新同步时钟。但它需要到10:32:33和10:33:53才能真正修好时钟。

你知道我怎样才能让时钟直接同步，几分钟后就可以了吗？

Answer 1

最后，我找到了一个保持时间同步的解决方案，并且在时间滞后(由DB节点检测到)的情况下强制立即同步时间。解决方案是重新启动The服务--模拟系统的重新启动。

我将数据库的systemd文件改为如下所示：

ExecStartPre=-+systemctl restart chronyd
ExecStartPre=/bin/sleep 5
ExecStart=/usr/local/bin/cockroach start ...

在/etc/chrony.conf文件中，我添加了以下行：

initstepslew 0.5 pool.ntp.org
makestep 0.5 -1

如果时间偏移大于0.5秒，这将迫使时间同步重新同步重新启动时间。

这最终使我的系统重新直接同步，然后立即重新启动数据库节点。

您可以查看这里以查找有关chrony.conf选项的更多信息。