[linux] reboot和shutdown-r的区别
google看看:
先搜英文的资料
http://askubuntu.com/questions/441969/what-is-the-difference-between-reboot-and-shutdown-r
(ubuntu论坛)
结论是:reboot uses shutdown -r
http://unix.stackexchange.com/questions/64280/what-is-the-difference-between-reboot-init-6-and-shutdown-r-now
(好像讨论的是linux问题)
结论是:reboot uses the shutdown command (with the -r switch).
再搜索中文的资料
http://bbs.chinaunix.net/forum.php?mod=viewthread&tid=1383005&highlight=reboot%2Bshutdown%2B-r
(freebsd论坛)
结论是:reboot命令重启动系统时是删除所有的进程,而不是平稳地终止它们
先看下freebsd 9.3
root@93a:~ # man reboot REBOOT(8) FreeBSD System Manager's Manual REBOOT(8) DESCRIPTION The halt and reboot utilities flush the file system cache to disk, send all running processes a SIGTERM (and subsequently a SIGKILL) and, respec- tively, halt or restart the system. The action is logged, including entering a shutdown record into the user accounting database. root@93b:~ # man shutdown SHUTDOWN(8) FreeBSD System Manager's Manual SHUTDOWN(8) DESCRIPTION The shutdown utility provides an automated shutdown procedure for super- users to nicely notify users when the system is shutting down, saving them from system administrators, hackers, and gurus, who would otherwise not bother with such niceties. -r The system is rebooted at the specified time.
本人英文较烂,按自己的翻译能力得知:
reboot过程会把系统的缓存写到硬盘,先发送SIGTERM再发送SIGKILL;
shutdown过程友好地通知线上用户,然后完好地保存。
结论即是:reboot与shutdown -r过程一致
下面是自己实际操作的结果
很明显reboot没有出现deamon平稳地终止过程,这是闹哪样啊。
顺便看下centos 6.7
[root@vhost102 ~]# man reboot DESCRIPTION These programs allow a system administrator to reboot, halt or poweroff the system. When called with --force or when in runlevel 0 or 6, this tool invokes the reboot(2) system call itself and directly reboots the system. Otherwise this simply invokes the shutdown(8) tool with the appropriate arguments. Before invoking reboot(2), a shutdown time record is first written to /var/log/wtmp [root@vhost102 ~]# man shutdown DESCRIPTION shutdown arranges for the system to be brought down in a safe way. All logged-in users are notified that the system is going down and, within the last five minutes of TIME, new logins are prevented. OPTIONS -r Requests that the system be rebooted after it has been brought down.
reboot --force 调用reboot重启系统,否则调用适当的shutdown参数
shutdown会安全地关机
结论即是:reboot与shutdown -r过程一致
reboot的过程
shutdown -r now的过程
总结一个吧
freebsd 9.3 reoot与shutdwon -r now不一致,reoot没有平稳地终止服务强制重启。
centos 6.7 reoot与shutdwon -r now一致,两者都是平稳地终止服务后重启。