AIX系统中的reboot命令必须谨慎的使用，前几天和同事在讨论之前的一个问题，说到为什么reboot之后机器就关机了，害的周末还得跑机房，印象中记得看到有一篇文章说过类似的问题，于是就man了下reboot命令。
# oslevel
5.3.0.0
# man reboot
Description
The reboot command can be used to perform a reboot operation if no other
users are logged into the system. The shutdown command is used when the
system is running and multiple users are logged into the system. Both
commands write an entry to the error log that states that the system was
deliberately temporarily disabled.
说的很明了了，reboot在当用户模式下是执行重启操作，但是在多用户情况下执行的是关机操作。