[Linux] 学习笔记第一篇——安装
环境：CentOS6.3 minimal

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1、下载

镜像地址：http://mirrors.stuhome.net/centos/6.3/isos/x86_64/
CentOS-6.3-x86_64-netinstall.iso
CentOS-6.3-x86_64-minimal.iso
CentOS-6.3-x86_64-bin-DVD1.iso
CentOS-6.3-x86_64-bin-DVD2.iso
CentOS-6.3-x86_64-LiveCD.iso
CentOS-6.3-x86_64-LiveDVD.iso

2、安装

安装环境：Oracle VM VirtualBox 4.2.6

3、注销、关机和重启

注销

$ logout
$ Ctrl + D

关机

$ poweroff

重启

$ reboot

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注：shutdown命令可以关闭所有程序，依照用户的需要，重新启动或关机。
1、立即关机：-h 参数让系统立即关机。范例如下:
$ shutdown –h now ← 要求系统立即关机
2、指定关机时间：time 参数可指定关机的时间，或设置多久时间后运行shutdown命令，范例如下:
$ shutdown now ← 立刻关机
$ shutdown +5 ← 5分钟后关机
$ shutdown 10:30 ← 在10:30时关机
3、关机后自动重启:-r 参数设置关机后重新启动。范例如下:
$ shutdown -r now ← 立刻关闭系统并重启
$ shutdown -r 23:59 ← 指定在23:59时重启动


Usage: shutdown [OPTION]... TIME [MESSAGE]
Bring the system down.


Options:
  -r                          reboot after shutdown
  -h                          halt or power off after shutdown
  -H                          halt after shutdown (implies -h)
  -P                          power off after shutdown (implies -h)
  -c                          cancel a running shutdown
  -k                          only send warnings, don't shutdown
  -q, --quiet                 reduce output to errors only
  -v, --verbose               increase output to include informational messages
      --help                  display this help and exit
      --version               output version information and exit


TIME may have different formats, the most common is simply the word 'now' which
will bring the system down immediately.  Other valid formats are +m, where m is
the number of minutes to wait until shutting down and hh:mm which specifies the
time on the 24hr clock.