Linux running level

The Linux system runs on a specified running level at any time, and different running-level programs and services are different. The work to be done and the purpose to be achieved are different, the system can switch between these running levels to complete different tasks.

Linux has a total of 7 running levels, namely 0-6, as follows:

0. Shutdown

1. Single User

2. There is no network service in the multi-user status

3. Multi-User statuses with Network Services

4. The system is not used and is retained to the user.

5. Graphic Interface

6. system restart

To change the system running level, run the init [0123456] command and add any number to change the running level.

Init [0123456] 

If it is set to 0, the PC will be shut down after the boot; if it is set to 6, the PC will be entangled between the restart and the boot.

View the current running level. command:

Runlevel 

Run the following command on ubuntu10.10:

N 2 

Indicates the last running and current running level, and N indicates no.

Then, how to modify these configuration files. It is generally in the/etc/inittab. But ubuntu10.10 does not have the file inittab, but is in the/etc/init/rc-sysinit.cnf file. For example:

# Default runlevel, this may be overriden on the kernel <br/> # command-line <br/> # or by faking an old/etc/inittab entry <br/> env default_runlevel = 2 

The default value is 2.

Ubuntu system running level:

0: system shutdown status

1: maintenance status of a single user or System

2 ~ 5. Multi-user status

6. Restart