Showing posts with label systems. Show all posts
Showing posts with label systems. Show all posts

November 17, 2021

Top 20 Apache ActiveMQ Interview Questions & Answers


Ques: 1). What exactly is ActiveMQ?


Apache Message-oriented middleware (MOM) is a type of software that transmits messages between applications, and ActiveMQ is one of them. ActiveMQ facilitates loose coupling of elements in an IT system using standards-based, asynchronous communication, which is frequently basic to business messaging and distributed applications. Messages are translated from sender to receiver using ActiveMQ. Instead of requiring both the client and the server to be online at the same time in order to interact, it can connect numerous clients and servers and allow messages to be queued.

AWS Lambda Interview Questions & Answers

Ques: 2). In Apache ActiveMQ, what are clusters?


Load balancing of messages on a queue between consumers is supported by ActiveMQ in a stable and high-performance manner. This scenario is known as the competing consumers pattern in corporate integration. The principle is illustrated in the diagram below: Interview questions for Activemq

The burden is distributed in an extremely fluid manner. In high-load periods, more consumers might be provisioned and joined to the queue without changing any queue setup, as the new consumer would behave like any other competing consumer. Better availability than load-balanced systems. To determine whether real-servers are offline, load balancers often use a monitoring system. A failed consumer will not compete for messages if there are competing consumers, so messages will not be given to it even if it is not monitored.

AWS Cloudwatch interview Questions & Answers

Ques: 3). What Is The Difference Between ActiveMQ And AmQP?


The Advanced Message Queue Protocol is a wire-level protocol for client-to-messaging-broker communication that serves as a specification for how messaging clients and brokers will interact.

AMQP is a message protocol rather than a messaging system like ActiveMQ.

Open wire protocols, such as OpenWire, a fast binary format, are supported by AMQP.

Stomp is a text-based protocol that is simple to implement.

MQTT is a little binary format designed for restricted devices over a shaky network.

AWS Cloud Support Engineer Interview Question & Answers

Ques: 4). What distinguishes ActiveMQ from other messaging systems?


  • It is a Java messaging service implementation, therefore it contains all of Java's features.
  • Extremely persistent
  • It has a high level of security and authentication.
  • Various brokers can form a cluster and collaborate with one another.
  • ActiveMQ offers a number of client APIs in a range of languages.

AWS Solution Architect Interview Questions & Answers

Ques: 5). What are the most important advantages of ActiveMQ?


  • Allows users to combine many languages with various operating systems.
  • Allows for location transparency.
  • Communication that is both reliable and effective
  • It's simple to scale up and offers asynchronous communication.
  • Reduced coupling

AWS RedShift Interview Questions & Answers

Ques: 6). What are ActiveMQ's biggest drawbacks?


It's a complicated mechanism that only allows one thread per connection.

AWS DevOps Cloud Interview Questions & Answers

Ques: 7), In ActiveMQ, what is a topic?


Virtual Topics are a hybrid of Topics and Queues, with listeners consuming messages from the queues as messages to the topic.

ActiveMQ assists in replicating and duplicating every message from the topic to the actual consumers queues.

AWS(Amazon Web Services) Interview Questions & Answers

Ques: 8). What is the difference between Activemq and Fuse Message Broker?


Multiple Protocol Messaging is a Java-based message broker that supports industry-standard protocols and allows users to choose from a wide range of client languages, including JavaScript, C, C++, and Python.

Fuse Message Broker is a distributor of FuseSource's Apache ActiveMQ, which it develops and updates as part of the Apache ActiveMQ community.

Bug fixes are more likely to come from the Fuse Broker release than from an official Apache ActiveMQ release.

AWS Database Interview Questions & Answers

Ques: 9). What exactly is KahaDB?


KahaDB is a file-based persistence database that runs on the same machine as the message broker. It has been designed to be persistent in a short amount of time. Since ActiveMQ 5.4, it has been the default storage mechanism. Compared to its predecessor, the AMQ Message Store, KahaDB consumes fewer file descriptors and recovers faster.


Ques: 10). What exactly is LevelDB?


LevelDB is a somewhat faster index than KahaDB, with slightly better performance figures. The LevelDB store will allow replication in forthcoming ActiveMQ releases.


Ques: 11). What's the difference between RabbitMQ and ActiveMQ?


ActiveMQ is a Java-scripted open-source message broker that is built on the Java Message Service client. The RabbitMQ protocol is based on the Advanced Message Queuing protocol.


Ques: 12). What are the benefits of using a combination of topics and queues instead of traditional topics?


There will be no lost communications even if a customer is offline. All messages are copied to the queues that have been registered by ActiveMQ.

A dead letter queue will be set up if a customer is unable to process a message. Without affecting the other consumers, the consumer can be resolved and the message forwarded to his own dedicated queue.

To implement a load balancing mechanism we can register multiple instances of a consumer on a queue.


Ques: 13). If the ActiveMQ server is unavailable, what should I do?


This begins with ActiveMQ's storage mechanism. Non-persistent messages are stored in memory under typical conditions, while persistent messages are stored in files, with their maximum limitations set in the configuration file's node. When the number of non-persistent messages reaches a specific threshold and memory becomes scarce, ActiveMQ will write the non-persistent messages in memory to a temporary file to free up space Despite the fact that they are all saved in files, the distinction between persistent messages and non-persistent temporary files is that persistent messages will be restored from the file after restart, whereas non-persistent temporary files would be removed immediately.


Ques: 14). What happens if the file size exceeds the configuration's maximum limit?


Set a 2GB persistent file limit and mass-produce persistent messages until the file exceeds its limit. The producer is currently prohibited, but the consumer can connect and consume the message as usual. The producer can continue to transmit messages after a portion of the message has been eaten and the file has been erased to make room, and the service will automatically revert to normal.

Set a 2GB limit on temporary files, mass-produce non-persistent messages, and write temporary files. When the maximum limit is reached, the producer is blocked, and consumers can still connect but not consume messages, or consumers who were previously sluggish consumers suddenly consume Stop. The complete system is linked, but it is unable to give services, causing it to hang.


Ques: 15). What is message-oriented middleware, and how does it work?


Message-oriented middleware (MOM) is a software or hardware framework that allows distributed systems to send and receive messages. MOM simplifies the development of applications that span different operating systems and network protocols by allowing application modules to be distributed across heterogeneous platforms. The middleware establishes a distributed communications layer that hides the intricacies of the multiple operating systems and network interfaces from the application developer.


Ques: 16). What is the benefit of Activemq over other options such as databases?


Activemq is a messaging system that allows two distributed processes to communicate successfully. It can keep messages in a database to communicate between processes, but you'd have to erase them as soon as they were received. For each message, this means a row insert and remove. When you try to scale that up to hundreds of messages per second, databases start to break down.

Message-oriented middleware, such as ActiveMQ, is designed to handle these scenarios. They assume that messages will be erased promptly in a healthy system and can make optimizations to prevent the overhead. It can also push messages to consumers rather than requiring them to poll for fresh messages via SQL queries. This minimises the amount of time it takes for new messages to be processed into the system.


Ques: 17). What are some of the platforms supported by ActiveMQ?


Some of the common platforms supported by ActiveMQ include:

Any java platform that has an update of 5.0 or more.

J2EE 1.4 is another platform

JMS 1.1

JCA 1.5 resource adaptor


Ques: 18). Make a distinction between ActiveMQ and Mule.


ActiveMQ is a messaging service with a lot of options for both the broker and the client. Mule, on the other side, is an ESB that may provide executive functionality to merely the broker by exchanging messages between various software components.

Mule's architecture is such that it is designed to provide a programming configuration that is feasible for integrating applications between a database and an operating system. Mule, on the other hand, does not support any form of native messaging system, hence it is typically used in conjunction with ActiveMQ. the user is required to introduce different and unique frameworks to define various boundaries for connectivity.


Ques: 19). What is the process for dealing with an application server using JMS connections?


The server session is created with the help of an application server, which then stores them in a pool. An association buyer uses the server's session to place messages in JMS sessions. The JMS session is created by a server session. The messaging audience is created by an application produced by application software engineers.


Ques: 20). What distinguishes ActiveMQ from the spread toolkit?


Spread Toolkit is a C++ library for informing, with only rudimentary support for JMS. It does not support robust informing, exchanges, XA, or JMS 1.1 in its entirety. It's also depending on a locally installed version of Spread inspiration. Apache ActiveMQ, on the other hand, is the JMS provider used in Apache Geronimo. It is J2EE 1.4 certified in Geronimo and is a completely pure version of the Java programming language. ActiveMQ supports real-time and persistent messaging, exchanges, XA, J2EE 1.4, JMS 1.1, JCA 1.5, and a slew of other features like Message Groups and Clustering.

November 15, 2021

Top 20 UX Design Interview Questions & Answers

Ques. 1). How would you improve our product's user experience(UX)?


Another area where preparation can truly help you succeed in the interview is here. Before you start, look over the product and think about how the user experience could be enhanced. You'll be able to speak in depth about how the interaction design or overall user experience could be enhanced by the time the question comes up.

Ques. 2). What is the difference between UX, UI, and Other Design Disciplines?


For this particular interview, this is a common question.

• The interviewer wants to know if you understand the tasks and responsibilities of a UX designer and how they differ from those of other designers, as well as if you can use UX design concepts to cooperate with other design disciplines. The trick is to first research the roles that this organisation demands, and then put out your answers.

• Try to explain that other disciplines are subsets of UX design and that design disciplines change with products, but that with UX design, the basic structure will remain consistent.

Ques. 3). How are you going to improve our product?


The interviewer wants to know if you did your homework on the job and the firm. If it's a major company, only provide an other answer if it's absolutely necessary, and only in conformity with the company's current trend. Diplomacy can also be used. Don't be scared to express yourself; yet, subtlety and precise language will be highly received. If it's a start-up, avoid criticising the product and instead focus on making it famous. Make sure you're familiar with the intended audience.

Ques. 4). How do you go about working on and processing a design?


You can also show them your portfolio in this scenario. Discuss some of your best work or a favourite design you've developed. This manner, you'll be able to show them how you work. Again, try to explain in terms of your work as a UX designer for that organisation in either situation.

Ques. 5). What is the User Experience (UX)?


When responding to this question, avoid using the standard definition from your textbook. Take a look at the other side of the coin. You've come because you require this position. So consider it from the standpoint of your profession.

Tell them why it's important to the project. Perhaps you could give an intriguing example to demonstrate how well you understand what you're going to perform. Make sure to include user research, information architecture, user interface design, experience strategy, usability, and interaction design in your plan.

Create a scenario in which you may describe how you will design for your audience. What important is that the user experience is centred on the user.

Ques. 6). Have You Run Into Any Issues While Developing Solutions for Your UX Design Project?


It is your responsibility as a UX designer to inform them about how you handle your assignments. Your interviewer wants to know how you work on a project, including your software processes and how you break down each project into smaller pieces before tackling it. You must outline how you set goals for each of your projects, as well as how you do research, produce prototypes, effectively communicate with your team about the goals, and how your team's combined efforts will lead to the final product.

You can tell them about a specific experience you had while working on a particularly difficult project. Tell them what went wrong, why it happened the way it did, how you fixed it, and how you'd use your knowledge in the future.

Ques. 7). How do you go about identifying the features you'd like to include in your design?


This is one of the most often asked questions in UX design interviews. Make sure you're ready for this. Specifically, they want to know if you can validate or reject a theory. This is to see how you came up with a different answer.

This is a difficult question to answer. It could be asked in a variety of situations. If this question was posed in the context of developing a new piece of software, you can always express your thoughts on what the minimum viable product should be (MVP).

You can concentrate on the principles of product strategy if it centres around an existing product. You can think about the response in terms of 'who the user is,' 'what are the aims of your user,' 'will the user be concerned about the feature, and how competent is the feature of fixing problems,' and so on.

This is where user research can be used to confirm design decisions. A great deal of user data aids designers in determining what has to be done next. If you have adequate data and a clear image of the user's goals, you can figure out which aspects are the most in line with those goals.

Ques. 8). What do you think the next big thing in UX will be?


They want to know how well you know what you're doing and whether you're thinking about what might happen in the future.

This is an excellent opportunity for you to demonstrate what you know and what you excel at. You could discuss new technologies that can help convert a design to code and save a lot of time.

On blogs like UXBooth, Design Modo, Intercom blog, User Testing blog, and others, you can always get inspiration and ideas on what drives and inspires you.

There are plenty additional online resources where you may get ideas for the latest trends and inspiration for what you might be asked in your next UX interview. Keep an eye out for motivation.

Ques. 9). What is "Design Thinking" and how does it work?


With the recent shift in the kind of employment people are choosing to explore their creative and imaginative sides, the UI/UX Design sector is the greatest option and has been fast growing. People are interested in UI/UX Design employment because of the high demand, as firms recognise the importance of designers in their strategy teams. The top ten UX UI designer interview questions are listed below.

Companies are recruiting more UI/UX designers to produce products that help them achieve their objectives while also meeting the expectations of their customers.

Companies have hired more UX designers as a result of the present COVID-19 issue.

Even if a person has excellent UI/UX design talents, they must have excellent communication skills to impress the interviewer. The online interview system has undoubtedly made it more difficult to communicate with the interviewer.

The interview process is a vital stage in getting a job as a UI/UX designer since it evaluates your logical reasoning, problem-solving ability, and creative thinking abilities, which are the most significant qualities of a UX designer, in addition to your portfolio.

Ques. 10). What is the difference between UI and UX design?


It appears to be a too broad and fundamental inquiry. Right? Just keep in mind that the interviewer does not want you to give a textbook definition to this question.

Use a basic example from your everyday life and describe it in a way that even a layperson may comprehend. For example, two teacups, one with a handle and the other without. Explain why the user prefers one cup over the other. Let the interviewer know that the major goal of UX design is to improve and enhance the consumer experience. The greatest way to demonstrate UX Design is to use real-world examples.

Ques. 11). How do you go about designing? Describe the situation in your own words.


Make sure you don't take the easy way out here. Simply provide the interviewer with a basic knowledge of the generic process and completely define it in your own words. He or she is curious about your approach to the procedure. Ensure that the research strategy is communicated. Discuss the design process with the interviewer and explain why you chose to design things the way you did. Finally, discuss testing and customer feedback. What methods did you use to test your design?

Explain your definition of UX design and how you see it in relation to people's requirements, as well as the necessity of getting to know the people you're designing for. As a UX designer, you must consider consumer feedback and tailor your product accordingly.

Also, incorporate some of the language features that designers use (not jargon). Describe how you moved from simple sketches (e.g., on a scrap of paper) to complex prototypes (e.g., using Adobe XD or Figma) to interactive prototypes. How many prototype revisions were there, and how did they differ from the final product?

Ques. 12). What is "Design Thinking" and how does it work?


Design Thinking is an important word that all UX designers should be familiar with, and it might be a knowledge testing question that is also vital for job selection. Design thinking is a method of problem-solving that is both practical and creative. It's all about gaining insight into your target audience's unmet wants. It's a type of solution-based procedure with the goal of achieving a positive future outcome.

Instead of going completely textbook here, say that it's a method in which people come first, and their preferences, needs, and behaviour affect the entire product design process.As a result, incorporate the following basic steps in your summary: -

1. Take advice from others.

2. Look for trends

3. Principles of Design

4. Make something concrete

5. Constantly iterate

Take a case study that you completed and explain the various stages of the process as well as the methodologies that you used at each step. Remember to explain the "Why" behind each activity as you go through the process.

Ques. 13). Failure of UX projects. What did you discover?


Remember that being a UX designer entails a lot of problem solving. As a result, make sure to lead the interviewer through the process. The interviewer will assess your problem-solving abilities, so remain calm and explain what, why, when, and how the project failed.

Address the problem and the grounds for its occurrence. Also, if you made a mistake, accept it and be honest about it. Designers value forthrightness. Giving a failure-related lesson demonstrates your integrity and commitment to your craft.

Ques. 14). Do you work well with others?


It's a question that practically every interviewer asks. Don't go too far with your response to this question. Instead, staying somewhere in the middle is always a good choice. If you concentrate on your own job, the interviewers may conclude that you are not suited to operate in a team environment.

As a result, attempt to frame your response by stating that while you appreciate working in collaborative workplaces, you know how to prioritise tasks and set your own deadlines when given individual responsibility. This will demonstrate that you aren't prone to extremes and can work in a variety of settings.

Ques. 15). What are some of your UX design inspirations?


When answering this question, be sincere and truthful. Do not be bashful about talking about design podcasts, blog posts, online chats, or in-person meetups. There is no right or incorrect response to this question because each designer finds inspiration in his or her own unique method.

Don't say something that you don't mean. Saying that you read all of the latest novels when you don't is a bad option because you won't be able to answer a specific follow-up inquiry in this scenario. Make things as simple as possible for yourself.

Ques. 16). Tell me about a time when a project didn't go according to plan. What did you do to make it better?


Interviewers frequently ask, "Tell me about a time when...", and you may be asked for multiple "times when." In this case, the interviewer is interested in learning more about your problem-solving abilities. They'll also want to see if you can maintain your composure under pressure. Use historical instances. Everyone has been dealt with a difficult undertaking at some point in their lives.

Consider bringing up a period when there was a snag in the process, budget cuts, or unforeseen circumstances. However, avoid pointing fingers. Also, make sure you don't offer an example when the problem was caused by your own irresponsibility.

Ques. 17). What are three of your greatest assets?


This is the time to brag about yourself. Just make sure that your skills match what the organisation is seeking for. We recommend going over the job description again to prepare for this question. Consider the following job description from Nextdoor in San Francisco:

Nextdoor is looking for someone who can develop "extremely engaging, enjoyable, and user-centered experiences," as you can see. They're looking for someone who can "guide team members" and "take part in cross-functional brainstorming, discussion, and design reviews." As a result, you may list your top three strengths as follows:

Empathy allows you to take a step back, set your biases aside, and prioritise the customer's requirements.

Leadership: At your previous position, you mentored several junior designers and enjoyed seeing them progress.

Collaboration: You enjoy discussing with other teams because each one has a unique set of skills and adds something new to the table.

When an interviewer asks about your strengths, you may expect them to inquire about your flaws as well.

Ques. 18). What is your greatest flaw?


It may seem paradoxical to tell a potential employer something you're not good at. It is, however, a common query. If at all feasible, frame your responses as good flaws. Take a look at NextDoor's job description in San Francisco to discover what qualifications they're seeking for:

They're looking for someone who can handle a "fast-paced startup," as you can see. This is code for "there's a lot going on and a lot of change," therefore one flaw may be: "If I'm not challenged or kept active, I grow bored."

This demonstrates to the interviewer that you can work in a fast-paced, demanding workplace. Alternatively, you may say:

"It's been suggested that I send too many emails outside of business hours."

This demonstrates that you are a hard worker who is always on, even when you are at home. (However, be sure it's the job you want!)

Ques. 19). How Do You Deal With Negative Feedback?


Say more than "well." Instead, explain you're open to all kinds of comments as long as it helps you improve as a UX designer. Give a few of examples of comments you've gotten on a project and how you dealt with it.

You could mention a prior supervisor who was quick to give critical input, but you preferred to call it "constructive criticism." Let's say you'd rather get input from internal sources than from actual customers once a product launches. You might inform the interviewer that you and your bosses are all on the same team and that you'd like to talk about anything you could improve on.

Ques. 20). Tell me about a time when you disagreed with a recommendation made by your team. What exactly did you do?


The best replies are those that are based on data. Keep that in mind. When possible, discuss how data and proven results can be used to make smart recommendations and business decisions.

In this case, you should discuss whether the recommendation was founded on empirical evidence or was entirely subjective. If possible, give an example of a subjective recommendation (e.g., "the boss likes the colour pink, so we're making the button pink").For instance, you may remark that your user research led you to disagree with the team's recommendation. Perhaps you've observed individuals engaging with prototypes and noticed that they prefer the colour blue over the colour pink. If possible, propose conducting another round of usability testing to compare a pink button against a blue button in an A/B test. Subjective opinions are less effective at resolving disagreements than objective data.

February 11, 2021

Top 20 Linux Interview Questions and Answers

Ques. 1): How can Linux be differentiated from other Operating Systems?
Linux is somewhat like other operating systems you might have used before, such as OS X, iOS or the Windows. Like other operating systems, Linux too has a graphical user interface. The types of software just like other operating systems have, such as the word processing applications.
 But Linux is different from other operating systems in many ways. First and foremost, Linux is open source software. The code used to create the OS is always free and available to the public to view, contribute and edit. Secondly, although the core pieces of the Linux OS are generally common, there are quite many distributions of Linux, which include different software options, which implies Linux is incredibly customizable. Linux users can also choose core components, such as the system displays graphics and other UI components.

Ques. 2): What is the basic difference between UNIX and Linux Operating System.
Linux Operating System is Free and Open Source Software, the kernel of which is created by Linus Torvalds and community. Well you cannot say UNIX Operating System doesn’t comes under the category of Free and Open Source Software, BSD, is a variant of UNIX which comes under the category of FOSS. Moreover Big companies like Apple, IBM, Oracle, HP, etc. are contributing to UNIX Kernel.

Ques. 3): What Is Shell Script?
A shell script, as the name suggests, is a script written for the shell. Script here means a programming language used to control the application. The shell script allows different commands entered in the shell to be executed. Shell script is easy to debug, quicker as compared to writing big programs. However, the execution speed is slow because it launches a new process for every shell command executed. Examples of commands are cp, cn, cd.

Ques. 4): What Are Pipes?
A pipe is a chain of processes so that output of one process (stdout) is fed an input (stdin) to another. UNIX shell has a special syntax for creation of pipelines. The commands are written in sequence separated by |. Different filters are used for Pipes like AWK, GREP.
e.g. sort file | lpr ( sort the file and send it to printer)

Ques. 5): What Stateless Linux Server? What Feature It Offers?
A stateless Linux server is a centralized server in which no state exists on the single workstations. There may be scenarios when a state of a partilcuar system is meaningful (A snap shot is taken then) and the user wants all the other machines to be in that state. This is where the stateless Linux server comes into picture.

·       It stores the prototypes of every machine.
·       It stores snapshots taken for those systems.
·       It stores home directories for those system.

Uses LDAP containing information of all systems to assist in finding out which snapshot (of state) should be running on which system.

Ques. 6): What Is Bash Shell?
Bash is a free shell for UNIX. It is the default shell for most UNIX systems. It has a combination of the C and Korn shell features. Bash shell is not portable. any Bash-specific feature will not function on a system using the Bourne shell or one of its replacements, unless bash is installed as a secondary shell and the script begins with #!/bin/bash. It supports regular and expressions. When bash script starts, it executes commands of different scripts.

Ques. 7): What Is A Zombie?
Zombie is a process state when the child dies before the parent process. In this case the structural information of the process is still in the process table. Since this process is not alive, it cannot react to signals. Zombie state can finish when the parent dies. All resources of the zombie state process are cleared by the kernel.

Ques. 8): Explain Each System Calls Used For Process Management In Linux.
System calls used for Process management:
·       Fork () :- Used to create a new process
·       Exec() :- Execute a new program
·       Wait():- wait until the process finishes execution
·       Exit():- Exit from the process
·       Getpid():- get the unique process id of the process
·       Getppid():- get the parent process unique id
·       Nice():- to bias the existing property of process

Ques. 9): How Do You Kill A Process?
kill -9 8 (process_id 8) or kill -9 %7 (job number 7)
kill -9 -1 (Kill all processes you can kill.)
killall - kill processes by name most (useful - killall java)

Ques. 10): What Is A Filesystem?
Sum of all directories called file system. A file system is the primary means of file storage in UNIX. File systems are made of inodes and superblocks.

Ques. 11): What Are Two Subtle Differences In Using The More And The Pg Commands?
With the more command you display another screenful by pressing the spacebar, with pg you press the return key. The more command returns you automatically to the UNIX shell when completed, while pg waits until you press return.

Ques. 12): We Saw the Mention On The Linux Bios Website About One Million Devices Shipped With Linux Bios. Could You Tell Us More About These Devices?
Yes, these are internet terminals that were built in India, based on the [x86 system-on-chip] STPC chip, I am told; also, there evidently is a Turkish-built digital TV that runs Linux BIOS. I have also heard that there are routers and many other embedded devices running Linux BIOS. I think at this point that 1 million is a low number. I am in contact with other set-top box vendors that are talking about numbers in the lOs of millions for their products. These numbers actually make the OLPC numbers seem small, which is in it amazing.

Ques. 13): What's Your Goal For Your Talk At Fosdem?
I’d like to communicate the basic ideas — that Linux is a good BIOS, and why; why Linux BIOS is built the way it is; where we are going; and how people can help. Most importantly, why it all matters — and it really matters a lot. We’re on the verge of losing control of the systems we buy, and we need to make a conscious effort, as a community, to ensure this loss of control does not happen. That effort will not be without some sacrifice, but if we are to maintain our ability to use and program our machines, and have fun with them, we have to act now. Because, if the computing business stops being fun, what’s the point$

Ques. 14): What Command Would You Use To Create An Empty File Without Opening It To Edit It?
You use the touch command to create an empty file without needing to open it. Answers a and e point to invalid commands, though either of these might actually be aliased to point to a real command. Answers b and c utilize editors, and so do not satisfy the requirements of the question. actually touch is used to change the timestamps of a file if its exits, otherwise a new file with current timestamps will be created.

Ques. 15): What Do You Type To Stop A Hung Process That Resists The Standard Attempts To Shut It Down?
The kill command by itself tries to allow a process to exit cleanly. You type kill -9 PID, on the other hand, to abruptly stop a process that will not quit by any other means. Also, pressing CtrI+C works for many programs. Answers b and d are only valid in some contexts, and even in those contexts will not work on a hung process.

Ques. 16): What Are The Techniques That You Use To Handle The Collisions In Hash Tables?
We can use two major techniques to handle the collisions. They are open addressing and separate chaining. In open addressing, data items that hash to a full array cell are placed in another cell in the array. In separate chaining, each array element consists of a linked list. All data items hashing to a given array index are inserted in that list.

Ques. 17): Why You Shouldn't Use The Root Login?
The root login does not restrict you in any way. When you log in as root, you become the system. The root login is also sometimes called the super user login. With one simple command, issued either on purpose or by accident, you can destroy your entire Linux installation. For this reason, use the root login only when necessary. Avoid experimenting with commands when you do log in as root.

Ques. 18): What Can You Type At A Command Line To Determine Which Shell You Are Using?
echo $SHELL-The name and path to the shell you are using is saved to the SHELL environment variable. You can then use the echo command to print out the value of any variable by preceding the variable’s name with $. Therefore, typing echo $SHELL will display the name of your shell.

Ques. 19): Is Linux Operating system Virus free?
No! There doesn’t exist any Operating System on this earth that is virus free. However Linux is known to have least number of Viruses, till date, yes even less than UNIX OS. Linux has had about 60-100 viruses listed till date. None of them actively spreading nowadays. A rough estimate of UNIX viruses is between 85 -120 viruses reported till date.

Ques. 20): How do you change permissions under Linux?
Assuming you are the system administrator or the owner of a file or directory, you can grant permission using the chmod command. Use + symbol to add permission or – symbol to deny permission, along with any of the following letters: u (user), g (group), o (others), a (all), r (read), w (write) and x (execute). For example, the command chmod go+rw FILE1.TXT grants read and write access to the file FILE1.TXT, which is assigned to groups and others.