Linux Run-Levels Questions

Linux Run-Levels Questions


01. Linux has ______ different run levels ( or operating modes).


Ans : Seven


02. Describe all different run levels in Linux

Ans : Linux has 7 different run levels
* rc0.d - System Halted
* rc1.d - Single User Mode
* rc2.d - Single User Mode with Networking
* rc3.d - Multi-User Mode - boot up in text mode
* rc4.d - Not yet Defined
* rc5.d - Multi-User Mode - boot up in X Windows
* rc6.d - Shutdown & Reboot


03. In Redhat/fedora Linux __________ command updates and queries runlevel information for system services


ans: chkconfig



04. Under which folder the service run settings are kept for run level 3 _

ans : /etc/rc.d/rc3.d


05. All files under /etc/rc.d/rc3.d that start with a capital S are the services that will _____ at this runlevel.


A. Skip
B. Start
C. Share
D. None

Ans : B


06. In Linux, which command will shift one run level to other ?


Ans: init


07. In Linux(Redhat), default runlevel is defined in _____________ file


Ans : /etc/inittab

08. Scripts that define runlevel 5 can be found in ____________


Ans : /etc/rc.d/rc.4 or /etc/rc.d/rc4.d

09. In Debian/ubuntu Linux __________ command installs and remove System-V style init script links.


ans: update-rc.d


Ref :

* http://www.networkclue.com/os/Linux/run-levels.aspx
* http://linux.com/news/enterprise/systems-management/8116-an-introduction-to-services-runlevels-and-rcd-scripts