Showing posts with label Linux. Show all posts
Showing posts with label Linux. Show all posts

November 23, 2021

Top 20 Aws Cloudwatch interview Questions & Answers

  

Ques: 1). What Is Amazon Cloudwatch and How Does It Work?

Answer:

CloudWatch is an AWS monitoring service that keeps track of your cloud resources and the applications you run on them. CloudWatch may be used to gather and track metrics, monitor log files, and generate alarms. EC2 instances, DynamoDB tables, and RDS DB instances may all be monitored with CloudWatch.

Amazon CloudWatch is a management tool for system architects, administrators, and developers, and it is part of the Amazon Web Services family.

 

AWS RedShift Interview Questions and Answers


Ques: 2). What's the difference between CloudTrail and CloudWatch, and how do I use them?

Answer:

CloudWatch keeps track of the health and performance of AWS services and resources and generates reports on them. CloudTrail, on the other hand, keeps track of all of the activities that take place in your AWS environment.


AWS Lambda Interview Questions & Answers


Ques: 3). What platforms are compatible with CloudWatch Logs Agent?

Answer:

The CloudWatch logs agent is compatible with a wide range of operating systems and platforms. The following is a list of similar items:

  • CentOS
  • Amazon Linux
  • Ubuntu
  • Red Hat Enterprise Linux
  • Windows


AWS Cloud Support Engineer Interview Question & Answers


Ques: 4). What Are Amazon Cloudwatch Logs, and What Do They Mean?

Answer:

Using your existing system, application, and custom log files, Amazon CloudWatch Logs allows you to monitor and troubleshoot your systems and applications. You may monitor your logs in near real time with CloudWatch Logs for specific phrases, values, or patterns. You could, for example, set an alarm for the amount of failures in your system logs or look at graphs of web request latency from your application logs. The original log data can then be viewed to determine the source of the problem. You don't have to worry about filling up hard discs because log data may be saved and accessed endlessly in very durable, low-cost storage.


AWS Solution Architect Interview Questions & Answers


Ques: 5). What Cloudwatch Access Management Policies Can I Implement?

Answer:

You can select which CloudWatch actions a user in your AWS Account can execute using CloudWatch's integration with AWS IAM. IAM cannot be used to restrict access to CloudWatch data for individual resources. You can't grant a person access to CloudWatch data for just one group of instances or a single LoadBalancer, for example. Permissions provided by IAM apply to all cloud resources used by CloudWatch. Furthermore, the Amazon CloudWatch command line tools do not support IAM roles.


AWS DevOps Cloud Interview Questions & Answers


Ques: 6). What is a CloudWatch Alarm, and how does it work?

Answer:

CloudWatch Alarms is a new feature that allows you to monitor CloudWatch metrics and receive warnings when they go outside of the levels (high or low thresholds) you designate. There can be several Alarms for each statistic, each with its own set of actions.

A CloudWatch Alarm's state is always one of three things: OK, ALARM, or INSUFFICIENT DATA. When the metric is inside the permissible range that you've set, the Monitor is in the OK condition. It enters the ALARM state when it hits a particular threshold. When the data needed to make a judgement is absent or incomplete, the monitor enters the INSUFFICIENT DATA state.


AWS(Amazon Web Services) Interview Questions & Answers


Ques: 7). What Is The Average Metric Retention Period?

Answer:

The following is how CloudWatch stores metric data:

For 3 hours, data points with a period of less than 60 seconds are available. These data points are bespoke measurements with a high resolution.

Data points with a period of 60 seconds (1 minute) are available for 15 days, 300 seconds (5 minutes) are available for 63 days, and 4) data points with a metric of 3600 seconds (1 hour) are available for 455 days (15 months). Data points with a shorter duration of publication are aggregated together for long-term storage.


AWS Database Interview Questions & Answers


Ques: 8). When should I use a custom metric instead of sending a log to Cloudwatch Logs?

Answer:

Custom metrics, CloudWatch logs, or both can be used to keep track of your data. If your data, such as OS process or performance measurements, is not already produced in log format, you may want to utilise custom metrics. You may also create your own app or script, or use one offered by an AWS partner. CloudWatch Logs can be used to store and save specific measurements as well as supplementary information.


ActiveMQ Interview Questions & Answers


Ques: 9). Is There Anything I Can Do With My Cloudwatch Logs?

Answer:

CloudWatch Logs can monitor and store logs to help you understand and operate your systems and applications better. No code modifications are necessary when using CloudWatch Logs with your logs because your existing log data is used for monitoring.

 

Ques: 10). What is Amazon CloudWatch Synthetics, and how does it work?

Answer:

You may use Amazon CloudWatch Synthetics to create canaries, which are programmable scripts that run on a schedule, to monitor your endpoints and APIs. Canaries follow the same paths as customers and do the same actions, allowing you to validate your client experience even when there is no customer activity on your apps. Using canaries, you can notice problems before your customers do.

Synthetic monitoring is a technique for assessing a website or online service's availability, performance, and functionality by mimicking visitor queries.

 

Ques: 11). Is it possible to use regular expressions with log data?

Answer:

Regular expressions are not supported by CloudWatch Metric Filters. Consider using Amazon Kinesis and connecting the stream to a regular expression processing engine to handle your log data with regular expressions.

 

Ques: 12). Canaries in Amazon CloudWatch Synthetics are what they sound like.

Answer:

Canaries are scripts that are written in Node.js or Python. Users construct Lambda functions in your account using Node.js or Python as a framework. The HTTP and HTTPS protocols are both supported by Canaries.

 

Ques: 13). How Do I Get My Log Data Back?

Answer:

The CloudWatch Logs console or the CloudWatch Logs CLI can be used to retrieve any of your log data. The Log Group, Log Stream, and time with which the log events are related are used to obtain them.

 

Ques: 14). What Are the Different Thresholds I Can Use To Set A Cloudwatch Alarm?

Answer:

When you create an alarm, you must first select the CloudWatch statistic that it will track. The next step is to select an evaluation period and a statistical value to assess. Set a target value and choose whether the alarm will be triggered if the value is more, equal, or less than that value to create a threshold.

 

Ques: 15). What is Amazon CloudWatch ServiceLens, and how does it work?

Answer:

Amazon CloudWatch ServiceLens is a new tool that allows you to visualise and analyse the health, performance, and availability of your applications in a single location. All public AWS Regions that offer AWS-X-Ray support Amazon CloudWatch ServiceLens.

 

Ques: 16). What are CloudWatch Metric Streams, and how can I use them?

Answer:

CloudWatch Metric Streams is a feature that lets you broadcast CloudWatch metrics endlessly to a location of your choice with very little setup and administration. It's a completely managed solution that takes care of everything for you, including writing code and maintaining infrastructure. With a few clicks, users can setup a metric stream to destinations like Amazon Simple Storage Service (S3). Users might also submit the analytics to a variety of third-party service providers to keep their operational dashboards up to date.

 

Ques: 17). What Can Amazon Cloudwatch Metrics Tell Me?

Answer:

CloudWatch allows you to monitor AWS cloud resources as well as the AWS packages you use. EC2 times, EBS volumes, ELBs, Autoscaling agencies, EMR process flows, RDS DB times, DynamoDB tables, ElastiCache clusters, RedShift clusters, OpsWorks stacks, Route 53 fitness assessments, SNS topics, SQS queues, SWF workflows, and Storage Gateways are among the AWS services and products for which metrics are automatically provided. You can also view custom metrics generated by your own applications and services.

 

Ques: 18). How do I send Grafana from CloudWatch metrics?

Answer:

1. Install Grafana : Follow the steps to Install Grafana.

2. Go to AWS -> IAM -> Policies.

3. Add below JSON in policy -> Create Policy:

{

   "Version": "2021-10-23", -- current Date

   "Statement": [

       {

           "Sid": "AllowReadingMetricsFromCloudWatch",

           "Effect": "Allow",

           "Action": [

               "cloudwatch:ListMetrics",

               "cloudwatch:GetMetricStatistics",

               "cloudwatch:GetMetricData"

           ],

           "Resource": "*"

       },

       {

           "Sid": "AllowReadingTagsInstancesRegionsFromEC2",

           "Effect": "Allow",

           "Action": [

               "ec2:DescribeTags",

               "ec2:DescribeInstances",

               "ec2:DescribeRegions"

           ],

           "Resource": "*"

       }

   ]

}

4. IAM -> Roles -> Create Role -> Select AWS Service / EC2

5. Attach Permission policies

6. IAM -> Users and click Add User ->Attach existing policies -> copy Access Key ID, your Secret Key

7. EC2 -> Instances-> Select Grafana Server and click on Actions -> Instance Settings -> Attach/Replace IAM Role -> Attach your Grafana IAM Role to the instance.

8. Log in to your Grafana Server using Terminal as root user and provide Access Key ID, your Secret Key:

# vim /usr/share/grafana/.credentials

aws_access_key_id = 000000000000

aws_secret_access_key = 0000000000

region = us-west-2


# chmod 0644 .credentials

9. Grafana -> Navigate to Data Sources -> Select CloudWatch Type

10. Create Dashboard -> Select Graph -> Select Panel Title -> edit and provide namespace.


Ques: 19). Is it possible to use IAM roles with the CloudWatch logs agent?

Answer:

Yes, the CloudWatch logs agent has access to both keys and IAM roles and is capable of supporting and working with IAM.

Amazon Key Management Service (AWS KMS) is a managed service that integrates with a number of other AWS services. You can use it to create, store, and control encryption keys in your applications to encrypt your data. AWS KMS Key Management Service is a service that allows you to manage your keys on Amazon Web Services.

 

Ques: 20). How does AWS CloudWatch handle authentication and access control?

Answer:

Use IAM users or roles to control who has access.

To manage access control, use Dashboard Permissions, IAM identity-based policies, and service-linked roles.

Permissions policies define who gets access to what and when.

Policies based on an individual's identity

Policies based on resources

You can't utilise CloudWatch Amazon Resource Names (ARNs) in an IAM policy because there aren't any. When designing a policy to control access to CloudWatch actions, replace the resource with a * (asterisk).




November 22, 2021

Top 20 Aws Cloud Support Engineer Interview Question & Answers

  

Ques: 1). What is the purpose of Amazon Web Services (AWS) cloud services?

Answer: 

"Storage," as this is the primary purpose of AWS cloud services. Customers can store several types of material on the Amazon online service, including videos, music files, movies, images, files, and documents. This is a common AWS cloud support engineer interview question that can be asked during the main portion of your interview.

 

BlockChain Interview Question and Answers


Ques: 2). In what way does Amazon Web Services appear to be ideal?

Answer: 

This is a very basic but common AWS Cloud Support Engineer interview question, and the candidate's response can be stated as follows:

The Amazon Web Servers are capable of performing a wide range of tasks. Customers can select the level of assistance and support they require from AWS based on the services they desire. Amazon Web Service (AWS) provides the following services:

  • High storage
  • Monitoring & Analytics
  • Security and safety
  • Networking
  • Databases
  • Compute power

These services will always be there for the clients of Amazon Web Services. For more details about the services, you can browse the official web page of Amazon Web Service (AWS).


AWS RedShift Interview Questions & Answers


Ques: 3). What Attracts You To This Position?

Answer:

I want to help the company grow and level up by providing safe database storage, content distribution, cloud services, and computer power. I've also been keeping up with your company's recent trends, and I've seen that what you're doing is exactly what I'm interested in. I'm excited to be a part of your team. I believe this position will provide me with a tremendous opportunity to help you improve in this field.


AWS Lambda Interview Questions & Answers


Ques: 4). What networking commands do you use on a daily basis to troubleshoot problems?

Answer:

When working with servers, whether real or virtual, the first command that comes to mind is traceroute, which may be used to find the request response path taken. Tracert is the corresponding command on Windows platforms.

Ping, ipconfig, and ifconfig are some other useful commands that deal with network communication, network addresses, and interface settings.

DNS commands – nslookup, Lookup of /etc/resolv.conf file in Linux systems to get details on DNS


AWS Cloudwatch interview Questions & Answers


Ques: 5). Tell us about your proudest achievement.

Answer:

My most significant accomplishment was in my former work as a cloud specialist. I worked for a firm that was experiencing a shortage of cloud professionals at the time. Adding more cloud professionals to the tea sounded expensive because the company was small. I recommended to the company's president how we could automate some tasks. I helped him because he didn't know what to do. Some operations, such as backups at specific intervals and resource pattern monitoring, become simple to automate. At the end of the day, the corporation was able to achieve its goal while spending very little money.


AWS Solution Architect Interview Questions & Answers


Ques: 6). What do you think the most difficult aspect of this job will be?

Answer:

Lack of experience and resources will be one of the primary issues that businesses will encounter in the near future. Technology is rapidly advancing as firms continue to shift more workload to the cloud. It's becoming difficult to keep up with the correct tools. This has necessitated further training in order for me to be prepared to deal with these difficulties if they affect our organisation.


AWS DevOps Cloud Interview Questions & Answers


Ques: 7). What services does AWS typically provide to its customers?

Answer: 

Everyone knows that Amazon Web Services (AWS) is a very dependable and trusted web service. It's a safe and secure web or cloud services platform that may propel your company to new heights of success. This type of question is the most popular and falls under the category of Amazon Support Engineer interview questions. This means that you must first clear your fundamentals in order to pass or crack this interview. You can find such basic questions among AWS cloud interview questions if you are prepared for an AWS interview.

To assist its clients, AWS provides computational power, database storage, content distribution, and a variety of other related support services. Customers all around the world have already chosen the AWS platform, products, and solutions to develop dependable applications with increased flexibility and reliability. It's a fantastic IT infrastructure platform for both small and large organisations.


AWS(Amazon Web Services) Interview Questions & Answers


Ques: 8). When a person types the domain name into a web browser, how can you bring the website content back to them?

Answer: 

As you may be aware, every website has its own domain name system (DNS). As a result, the DNS and each website would be assigned a unique internet protocol or IP address. When entering a domain name into a web browser, the following scenarios may arise:

  • Your input or signal will be received as a request by the web server hosting services. Following that, the web server hosting firm will undoubtedly respond to your request with appropriate outcomes.
  • When you use a browser, it sends a request to the internet protocol address, which is linked to the domain name automatically.
  • The IP address is sometimes returned to the user by the domain name system.
  • To deliver back the website content to the users, the web browser will contact a domain name system.

The salary of a cloud support engineer in AWS is determined by your abilities and performance during the AWS support interview. So, if you want a higher income in your AWS work, make sure you answer the interviewer's questions properly and confidently.


AWS Database Interview Questions & Answers


Ques: 9). Give some instances of typical networking commands you've used.

Answer:

It's worth noting that the AWS stack is mostly based on Linux, and its cloud design makes it extremely network-dependent. As a result, regardless of your history as a system administrator, database administrator, or bigdata administrator, your AWS interview could be about networking. Learn how to use these basic networking commands:

The first step when a system is unreachable is to ping the host to ensure it is up and functioning.

ping host – This pings the host and output results

Domain related commands as AWS has become preferred hosting for major itnernet based companies, SaaS firms

To get DNS information of the domain use – dig domain

To get whois information on domain use – whois domain

Host reverse lookup – dig -x host

Download file – wget file

To continue stopped download – wget -c file


ActiveMQ Interview Questions & Answers


Ques: 10). What does the term "fault tolerant" mean?

Answer: 

When a set number of failures and issues occur, the fault tolerant process is used to control or manage the faults. It's one of the AWS Cloud's most critical self-healing features. This has become a crucial Amazon AWS cloud support engineer interview question and answer because, while the question appears easy, the answer is really complex.

It is a system property that allows a system to work or continue to work in the face of numerous failures at any moment. It is a computer system capability that makes the work of users much more reliable. Such systems are intended to safeguard any present functional system against numerous failures that may occur at any given time. It ensures that any network or system maintains the needed level of continuity in order to avoid the negative effects of interruptions.

 

Ques: 11). What exactly is a procedure? In Linux, how do you manage processes: -

Answer:

When a command is issued in a Linux/Unix based OS, a process is launched or created. In simple terms, an instance of a programme is produced while it is running in an operating system. This is how it works. Process management commands are useful in Linux for managing processes.

ps – this is the commonly used process management command to start with. ps command provides details on currently running active processes.

top – This command provides details on all running processes. ps command lists active processes whereas top lists all the processes (i.e) activity of processor in real-time. This includes details on processor and memory being used.

kill – To kill a process using the process id kill command is used. ps command provides details on process id. To kill a process issue kill pid.

killall proc – This command is same as kill command. To kill all the processes by name proc we can use this

 

Ques: 12). In Amazon Web Services, Emphasize The Importance Of Buffer.

Answer:

An Elastic Load Balancer ensures that incoming traffic is spread as efficiently as possible across multiple AWS instances. A buffer will synchronise several components and make the setup more elastic in the event of a burst of load or traffic. The components are prone to receiving and processing requests in an unreliable manner. The buffer produces an equilibrium between diverse devices and crafts them to function at the same rate, allowing for faster service delivery.

 

Ques: 13). What Is An Amazon Web Services Availability Zone?

Answer: 

A collection of your AWS resources is made up of availability zones (within a region). For high availability and fault tolerance, properly built applications will use several availability zones. Each AZ has a low-latency direct connection to the others, and each AZ is separated from the others to ensure fault tolerance.

 

Ques: 14). What Happens When A User Types A Domain Name Into A Web Browser? 

Answer:

A DNS server is contacted by the web browser, which requests the IP address associated with the domain name.

The IP address is returned to the Browser by the DNS server.

A request (for content) is sent by the browser to the IP address associated with the domain name.

The request is received by the web server holding web content, which then provides the web content back to the user.

 

Ques: 15). What are the various kinds of routing protocols?

Answer:

The routing protocol is a crucial word that describes how different routers communicate. The routing protocol can be implemented by two nodes in a computer network. The following are some of the most often used routing protocols:

  • Routing information protocols (RIP)
  • Interior Gateway Protocol (IGP)
  • Open shortest path first (OSPF)
  • Exterior Gateway Protocol (EGP)
  • Border Gateway Protocol (BGP)
  • Intermediate system to intermediate system (IS-IS)

These are some of the most commonly utilised routing kinds among system users. The interviewer may pose this topic as one of the most typical AWS cloud support engineer interview questions. So, remove your doubts regarding the network, infrastructure, and other related topics before embarking on such interviews.

 

Ques: 16). What Does The Elasticity Concept Mean For AWS Consumers and Enterprise Users?

Answer:

Elastic systems allow for the rapid addition and subtraction of servers as demand (user base) on a web application increases and drops. Getting rid of unused servers might save a lot of money.

 

Ques: 17). What is the primary distinction between a private and a public subnet?

Answer:

A private subnet normally directs traffic to a NAT instance. In the private subnet, only private IP and internet traffic is routed. A public subnet, on the other hand, requires a public IP address to communicate. The major distinction between a private and a public subnet is this.

 

Ques: 18). How would you persuade a customer to switch to AWS?

Answer: 

These types of questions might be posed during your interview to assess your mental agility, persuasion power, and speaking ability. As a candidate, you must remain cool and optimistic under such circumstances. If this question is asked during your interview, you must respond honestly. You can state things like "I have experience dealing with such customers" and "I have knowledge and expertise dealing with such consumers," and so on in your response. You can persuade customers by describing the capabilities and advantages of using the AWS cloud. As a result, job candidates can readily respond to this question based on their degree of thinking and speaking ability.

 

Ques: 19). Do you understand how the internet works in your area?

Answer: 

There are several internet tiers and web servers available all over the world, which serve as the internet's communication path. Without the internet's ingenuity, sharing could not have progressed as quickly as it has. 

Circuit switching is a word used on the internet to describe how the internet works in your current context. Another internet technology is packet switching, which makes it much easier for the internet to communicate or distribute information. This is one of the most common AWS cloud support engineer interview questions because it gives you some fundamental internet knowledge.

Packing switching is the process of separating a single internet server into numerous servers. There is no requirement for a physical path for the computer. The internet's supporting equipment would be sufficient to enable better and more dependable internet sharing among a large number of computers.

 

Ques: 20). In Linux or UNIX-based operating systems, how can you easily manage processes?

Answer:

When a user types a command into a Unix operating system, it starts working. When an operating system is started, an instance is created automatically. To manage processes in Linux OS, I would use the PS processing command. This command displays information about the currently running processes and activities. When running Linux, I can also use TOPIS as a process management tool. 

This command can be used to acquire statistics about the operating system's activity. To kill running processes, I would also use the Kill command. In a Linux-based operating system, press Ctrl+Alt+Del to terminate all programmes. I would use the killall command. With these commands, I would be able to take full control of the operating system and manage its processes effectively.

 

 

February 11, 2021

Top 20 Linux Interview Questions and Answers

 
Ques. 1): How can Linux be differentiated from other Operating Systems?
Answer: 
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.
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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.

Features:
·       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?
Answer: 
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?
Answer: 
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.
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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?
Answer: 
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.