interview question for linux-4

 How are devices represented in linux?

All devices are represented by files called special files that are located in /dev directory.

Why is LVM is required ?
Ans: LVM stands for Logical Volume Manager , to resize filesystem’s size online we required LVM partition in Linux. Size of LVM partition can be extended and reduced using the lvextend & lvreduce commands respectively.

how you will Create new folder / directories and how to remove file and folder in linux? Create new folder or directory, if they do not already exist already? 

#mkdir  (option) (folder name)

To Remove files & folders:

#rm –rf (file/directory)

What is LILO?

LILO is Linux Loader is a boot loader for Linux. It is used to load Linux into the memory and start the Operating system.

What is LD_LIBRARY_PATH?

Answer - LD_LIBRARY_PATH is an environment variable. It is used for debugging a new library or a non standard library

What is NFS?

Answer - NFS is Network File system. It is a file system used for sharing of files over a network.

What is Kernel?

Answer - Kernel is used in linux like systems and is considered to be the heart of the operating system.

What is Bash Shell?

Answer - Bash is a free shell for linux. It is the default shell for most linux systems. It has a combination of the C and Korn shell features.

How to set the umask permanently for a user?
Ans: To set this value permanently for a user, it has to be put in the appropriate profile file which depends on the default shell of the user.

What are the process states in Unix?

As a process executes it changes state according to its circumstances. Unix processes have the following states:

Running : The process is either running or it is ready to run .
Waiting : The process is waiting for an event or for a resource.
Stopped : The process has been stopped, usually by receiving a signal.
Zombie : The process is dead but have not been removed from the process table.