# 内核启动顺序

## CentOS和Redhat系统

第一步，通过 `/boot/vm` 进行启动 `vmlinux` 。

第二步，初始化 `init /etc/inittab` 。

第三步，启动相应的脚本，并打开终端。

```bash
#按顺序
rc.sysinit
rc.d
rc.local
```

第四步，启动 `login` 登录界面。

第五步，在用户登录后依次执行sh脚本。

```bash
#按顺序
/etc/profile.d/file
/etc/profile
/etc/bashrc
/root/.bashrc
/root/.bashrc_profile
```

Redhat中的运行模式2、3、5都把/etc/rc.d/rc.local做为初始化脚本中的最后一个，所以用户可以自己在这个文件中添加一些需要在其他初始化工作之后，登录之前执行的命令。


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