我听说“shutdown -h now”不是一个优雅的关闭命令，因为它对所有进程执行类似于“kill -9”的操作，而不是“kill -15”。
这是真的吗，如果是这样，有什么更优雅的关闭方式来确保一切都有时间自我清理？
Ps 主要使用 CentOS、Ubuntu 和 Debian。
Cak*_*mox 15
shutdown -h now将调用/etc/rc.d/rc或/etc/init.d/rc。该rc脚本将调用新运行级别的终止脚本（0 代表-h，6 代表-r），然后是任何启动脚本。
根据您的发行版，您会看到S30killprocs或S00killall类似的东西。这是在调用所有终止脚本以尝试依次优雅地停止每个服务之后发生的。它将kill -15首先尝试，然后是kill -9。
简短的回答：shutdown -h now或者shutdown -r now是优雅的。 halt并且reboot曾经是不优雅的，但shutdown除非您使用该-f选项，否则他们只会打电话给您。
mai*_*ilq 13
不，那不是真的。shutdown更改 init 级别，然后运行所有关闭脚本。这些脚本做什么取决于脚本。但它们通常不会终止进程，而是向它们发送结束信号。
所以这是手册摘录shutdown：
shutdown brings the system down in a secure way. All logged-in users
are notified that the system is going down, and login(1) is blocked.
It is possible to shut the system down immediately or after a specified
delay. All processes are first notified that the system is going down
by the signal SIGTERM. This gives programs like vi(1) the time to save
the file being edited, mail and news processing programs a chance to
exit cleanly, etc. shutdown does its job by signalling the init
process, asking it to change the runlevel. Runlevel 0 is used to halt
the system, runlevel 6 is used to reboot the system, and runlevel 1 is
used to put to system into a state where administrative tasks can be
performed; this is the default if neither the -h or -r flag is given to
shutdown. To see which actions are taken on halt or reboot see the
appropriate entries for these runlevels in the file /etc/inittab.