Optimizing ubuntu-Modifying the boot level

A modified Ubuntu boot level

sudo apt-get install sysv-rc-conf

Perform:

Sysv-rc-conf

Hit X to start the boot.

Two boot levels

Ubuntu Default boot level is 2

[Email protected]:/etc/rc2.d# runlevel

N 2

Ubuntu Default boot RunLevel is 2, you can use RunLevel to view the current default run level.

The Debian system (Ubuntu is Debian based) Linux has been started by default with RunLevel, and runlevel definitions are also different from Redhat. The runlevel level of Debian is defined as follows:

0–halt, Shutdown mode

1–single, single-user mode

2-full Multi-User with Display Manager (GUI)

3-full Multi-User with Display Manager (GUI)

4-full Multi-User with Display Manager (GUI)

5-full Multi-User with Display Manager (GUI)

6–reboot, restart

You can see that there is no difference in the 2~5 level. They are multi-user mode, which is not the same as Linux in general. The runlevel level of Redhat is defined as follows:

0: Turn off the machine. The system default run level cannot be set to 0, otherwise it cannot be started.

1: Single user mode, only allow the root user to maintain the system.

2: Multi-user mode, but cannot use NFS (equivalent to a network Neighborhood under Windows)

3: Multi-user mode for character interface.

4: Not defined.

5: Multi-user mode for graphical interface.

6: Reboot. You cannot set the system default run level to 0, or it will restart all the time.

In addition, most Linux uses a mechanism called System V to start the runlevel, while Ubuntu initiates the process using upstart instead of Init. So there is no Inittab file to change the default runlevel. The default RunLevel file for Ubuntu is/etc/init/rc-sysinit.conf.

Optimizing ubuntu-Modifying the boot level