如何强制 chrony 现在同步？
How to force chrony to sync NOW?
我运行一个需要及时的数据库集群。可悲的是，有时我的 VM 托管商正在将具有此类 DB 节点的 VM 移动到另一台主机，然后时间缺少一秒或更长时间。然后我的数据库节点关闭并由 systemd 重新启动。
我的 systemd 文件包含这个：
ExecStartPre=-+/usr/bin/chronyc -a makestep
ExecStart=/usr/local/bin/.......
我希望在这种时滞关闭数据库后立即同步我的时间。但由于我的日志 最多需要 7 分钟才能识别并修复差异。我的数据库在每次重启时检测到间隙并再次关闭。最后，我得到了这个 chronyd 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 10:25:51 检测到这个问题。由此，在每次数据库重启之前，上述命令被执行多次以重新同步时钟。但它需要直到 10:32:33 和 10:33:53 才能真正最终修复时钟。
知道如何强制时钟在几分钟后直接同步吗？
我终于找到了一个解决方案来保持 chrony 并在出现时间滞后（由 DB 节点检测到）的情况下强制立即同步。解决方案是重启 chronyd 服务 - 模拟系统重启。
我将数据库的 systemd 文件更改为如下所示：
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，这会强制 chronyd re-sync 重新启动的时间。
这终于让我的系统直接re-sync然后马上重启数据库节点
您可以查看 here 以找到有关 chrony.conf 选项的更多信息。
我运行一个需要及时的数据库集群。可悲的是，有时我的 VM 托管商正在将具有此类 DB 节点的 VM 移动到另一台主机，然后时间缺少一秒或更长时间。然后我的数据库节点关闭并由 systemd 重新启动。
我的 systemd 文件包含这个：
ExecStartPre=-+/usr/bin/chronyc -a makestep
ExecStart=/usr/local/bin/.......
我希望在这种时滞关闭数据库后立即同步我的时间。但由于我的日志 最多需要 7 分钟才能识别并修复差异。我的数据库在每次重启时检测到间隙并再次关闭。最后，我得到了这个 chronyd 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 10:25:51 检测到这个问题。由此，在每次数据库重启之前，上述命令被执行多次以重新同步时钟。但它需要直到 10:32:33 和 10:33:53 才能真正最终修复时钟。
知道如何强制时钟在几分钟后直接同步吗？
我终于找到了一个解决方案来保持 chrony 并在出现时间滞后（由 DB 节点检测到）的情况下强制立即同步。解决方案是重启 chronyd 服务 - 模拟系统重启。
我将数据库的 systemd 文件更改为如下所示：
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，这会强制 chronyd re-sync 重新启动的时间。
这终于让我的系统直接re-sync然后马上重启数据库节点
您可以查看 here 以找到有关 chrony.conf 选项的更多信息。