Latest Linux Threads Interview Questions
Q – 1 How to install certificate in ftp rhel5?
Ans- Try on your own
Q – 2 Suppose we have three threads T1, T2 and T3 which perform sequentially one after another is their any benefit of using thread over here rather than having a single process?
Ans- here T1, T2 and T3 as a thread consumes less memory and more speed but as a process it consumes more memory.
Example:
Multiple threads can be run within a single memory allocations. but process needs seperate memory allocations for each process.
Q – 3 What is the use of thread over process?
Ans- Thread is an executable entity but it is bound to its parent process. now there are two types of threads.
1. user space threads and
2. kernel thread
now the kernel threads are actually known as light weight processes.
why light weight????
>>>> as it’s context switching times is lesser than all other process.
now why the context switching time is less????
>>>>> as process have there own process address space and maintains many more things like userID, ProcessID, groupID,
number of files opened, reisters and blah, blah
whereas thread shares it’s parent process’s address space and mainly contains three things like own stack, registers and thread related data.
so more things to swap need more time that’s why thread’s context switching time is less compared to that of a process. now the answer, use of thread: thread are used to provide multi-programming environment.
ok, now u ppl would think that, it can also be done creating new processes (using fork())
yes we can, but as i told earlier that the context switch time for threads are very less. moreover the inter-thread communication is more easier than inter-process communication as all threads of a single process uses the same address space.
Q – 4 What is crondtab daemon?
Ans- The cron daemon reads the /etc/cronlog.conf configuration file provided by the user to log the information. If a configuration file has not been created, then the cron daemon creates a log of its activities in the
/var/adm/cron/log file.
The cron daemon reads the configuration file when it is activated and when it receives the hangup signal.
If the cron daemon is not able to create or open the user-specified logfile, then it creates a log of its activities in the /var/adm/cron/log file.
Q – 5 At installation, Red Hat Fedora Linux creates a symbolic link called _____ to the appropriate cd-rom device?
Ans- It creates dev/cdrom
However on a newer system it’s dev/sr0
Q – 6 An extended partition can contain many sub partitions called_______?
Ans- extended partition contain logical partition
Q – 7 A _____Bios automatically assigns the necessary configuration information (IRQs I/O addresses, and DMAS) to devices and avoid conflicts?
Ans- BIOS Has a set of routine to initialize the Bare hardware.
If “automatically assign” means initialization then the proposition is right. Else… The BIOS inits the system resources and stores the values in NVRAM(CMOS) the screen you see for configuring the SYSTEM parameter is a depict of CMOS/NVRAM not the BIOS.
When you configure the System, the post-BIOS routines read those and prepares the system for start-up.
Q – 8 When performing a Linux installation the____ command can be typed to start the installation without framebuffer support?
Ans- vga=xxx where XXX is resolution mode
Ex. XXX=791 for 1024×768 resolution
Q – 9 A _____ cpu is a cpu that has a speed greater than the speed that was originally intended for the processor?
Ans- its called overclocking, generally the processor is set to a low clock rate which can be increased to higher clock frequencies. Example a P4 3Ghz processor could be overclocked to 4.2 Ghz but it requires a lot of skills and
additional heat sinks to dissipate the energy.
Also, it can lead to permanent damage of processor
Q – 10 What is the scope and packages being offered after the Linux course completion?
Ans- You will concentrate on shell scripting and database like Oracle, Sql etc., The Redhat offer RHSA, RHSS courses
Q – 11 What are different ways of creating threads?
Ans- In a process at least one thread will always be there.
So i think, when we create a new process using fork() system, this is also a thread creation (single thread only).
Q – 12 What is LD_LIBRARY_PATH?
Ans- This is one system administrator’s point of view why LD_LIBRARY_PATH, as frequently used, is bad. This is written from a SunOS 4.x/5.x (and to some extent Linux) point of view, but this also applies to most other UNIXes.
LD_LIBRARY_PATH is an environment variable you set to give the run-time shared library loader (ld.so) an extra set of
directories to look for when searching for shared libraries. Multiple directories can be listed, separated with a colon (:). This list is prepended to the existing list of compiled-in loader paths for a given executable, and any system default loader paths.
For security reasons, LD_LIBRARY_PATH is ignored at runtime for executables that have their setuid or setgid bit set.
This severely limits the usefulness of LD_LIBRARY_PATH.
Q – 13 How to recover the linux system after it was crashed?
Ans- boot the system through 1st CD and after give time and all setting then on installing SCREEN type ‘rescue’ for go to rescue mode, then type #mount /chroot/sysimage then enter know what ever problem u have u can trableshoot either filesystem or grub if it is related to grub then type ‘#fdisk -l’ to see the partition type then install grub by ‘grub-install /dev/hda,b,c’ or what ever ……..