Red Hat RH033 Online Practice Questions and Exam Preparation

Red Hat RH033 Online Questions & Answers

• Question 141:

  You work as a Network Administrator for Maverick Inc. The company has a Linux-based network.

  You are working on a Linux computer. You want to see the environment variables that are set on your computer. Which of the following commands will you use?

  A. env
  B. rm
  C. ls
  D. echo $shell
  A. env

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  Explanation/Reference:

  The env command is used to list the environment variables that are set on a Linux computer.

  The programs that run on a Linux computer are known as processes. When a user starts a program, a new process is created. This process runs within what is called an environment. A user can set parameters in this environment so that the

  running program can find the desired values. The following syntax is used to set a parameter to a variable:

  VARIABLE=value

  This would set a parameter by the name VARIABLE with the value that you provide. Some of the commonly used environment variables are HOME, PATH, PS1, etc. Answer option B is incorrect. The rm command is used to delete files from a

  directory on a Linux computer.

  Answer option C is incorrect. The ls command is used to list files on a Linux computer. Answer option D is incorrect. The echo $shell command will provide the name of the current shell that a user is using.

• Question 142:

  Which of the following commands is used to make traceroute wait 5 seconds for a response to a packet?

  A. traceroute -w
  B. traceroute -T
  C. traceroute -q
  D. traceroute -r
  A. traceroute -w

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  Explanation/Reference:

  The traceroute -w command is used to make traceroute wait 5 seconds (default) for a response to a packet.

  What is traceroute?

  Traceroute is a route-tracing utility that displays the path an IP packet takes to reach its destination.

  It uses Internet

  Control Message Protocol (ICMP) echo packets to display the Fully Qualified Domain Name (FQDN) and the IP address of each gateway along the route to the remote host. Traceroute sends out a packet to the destination computer with the

  TTL field value of 1. When the first router in the path receives the packet, it decrements the TTL value by

  1. If the TTL value is zero, it discards the packet and sends a message back to the originating host to inform it that the packet has been discarded. Traceroute records the IP address and DNS name of that router, and sends another packet with a TTL value of

  2. This packet goes through the first router, and then times out at the next router in the path. The second router also sends an error message back to the originating host. Now, the process starts once again and

  traceroute continues to send data packets with incremented TTL values until a packet finally reaches the target host, or until it decides that the host is unreachable. In the whole process, traceroute also records the time taken for a round trip

  for each packet at each router.

  Answer option B is incorrect. The traceroute -T command uses the TCP/SYN packets for probing.

  Answer option C is incorrect. The traceroute -q command sets the number of probe packets per hop.

  The default value is 3.

  Answer option D is incorrect. The traceroute -r command bypasses the normal routing tables and sends the probe packet directly to a host on an attached network. If the host is not on a directly-attached network, an error is returned. This

  option can be used to ping a local host through an interface that has no route through it.

• Question 143:

  Which of the following commands will you use to lists the jobs that are running in the background and in the foreground?

  A. top
  B. bg
  C. job
  D. jobs
  D. jobs

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  Explanation/Reference:

  The jobs command lists the jobs that are running in the background and in the foreground. If the prompt is returned with no information, no jobs are present.

  Syntax:

  jobs [-p | -l] [-n] [-p] [-x] [job id]

  Some important options used with jobs command are as follows:

  

  Answer option A is incorrect. The top command is used to produce a frequently-updated list of processes. By default, the processes are ordered by percentage of CPU usage, with only the "top" CPU consumers shown. This command shows how much processing power and memory are being used, as well as other information about the running processes. The following figure demonstrates the output of the top command:

  

  Answer option B is incorrect. The bg command can be used to resume in the background when a process is suspended. Answer option C is incorrect. There is no such command as job.

• Question 144:

  Mark is a newly appointed Network Technician for McNeil Inc. The company has a Linux- based network. He is working on the Red Hat operating system. He wants to sort a file named marketing.txt in the reverse alphabetical order. Which of the following commands should Mark use to accomplish this task?

  A. sort -u marketing.txt
  B. sort marketing.txt
  C. sort -n marketing.txt
  D. sort -r marketing.txt
  D. sort -r marketing.txt

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  Explanation/Reference:

  This command will run sort on the file marketing.txt and sort the file in the reverse alphabetical order.

  Answer option B is incorrect. sort with no options is used to sort file alphabetically. It will not sort the file in the reverse alphabetical order.

  Answer option C is incorrect. The -n option used with the sort command sorts the text numerically, instead of by characters.

  Answer option A is incorrect. The -u option with sort removes duplicate lines from the output.

• Question 145:

  Which of the following commands is used to securely copy files from one host to another over the network?

  A. ls
  B. cat
  C. mutt
  D. scp
  D. scp

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  Explanation/Reference:

  The scp command is used to copy files from one host to another over the network.

  What is the scp command?

  The scp command is used to copy files over ssh connections. This is pretty useful if a user wants to transport files between computers, for example, to backup a file. The scp command uses the ssh command to copy files over the network.

  Syntax:

  # scp [options] source destination

  Where, source refers to the file which a user wants to copy from his current computer/directory, and destination refers to the home directory of the remote system where a user wants to copy the file.

  Some important options used with the scp command are as follows:

  

  Answer option A is incorrect. The ls command in Linux lists information about files (the current directory by default).

  Answer option C is incorrect. The mutt command is used to manage email within a text only environment.

  Answer option B is incorrect. The cat command is used to join multiple files together and display the result on the screen.

• Question 146:

  You are required to define a cron job that executes at 5:30 PM every Friday. Which of the following time specifications can be set to accomplish the task?

  Each correct answer represents a complete solution. Choose two.

  A. 17 30 * * 6
  B. 30 17 * * 5
  C. 17 30 * * FRI
  D. 30 17 * * FRI
  B. 30 17 * * 5
  D. 30 17 * * FRI

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  Explanation/Reference:

  According to the question's requirement, the following time specifications can be set for the cron job: 30 17 * * 5 30 17 * * FRI In this time specification, you can define five parameters. The first two parameters define minutes and hours of the day. The last or the fifth parameter shows the day of the week. It can be the name or the number of a day. Numbers 0 and 7 are for Sunday, whereas from Monday to Saturday, the numbers are from 1 to 6.

• Question 147:

  Which of the following commands can be used by a user to display the list of contents existing in his current user account?

  Each correct answer represents a complete solution. Choose all that apply.

  A. echo *
  B. ls ~
  C. ls *
  D. pwd
  A. echo *
  B. ls ~

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  Explanation/Reference:

  The ls ~ and echo * commands can be used by a user to display the list of contents existing in his current user account. While ~ forces a command to perform queries in the user's home directory, ls displays the contents of the home directory.

• Question 148:

  Which of the following statements are true about open source software?

  Each correct answer represents a complete solution. Choose two.

  A. In OSS access to source code by third parties commonly requires the party to sign a nondiscloser agreement.
  B. It is software whose license does not allow for the distribution of the software source's source code.
  C. Open source software and its source code must be freely distributable.
  D. In OSS all users must be able to modify the source code and create derived works.
  C. Open source software and its source code must be freely distributable.
  D. In OSS all users must be able to modify the source code and create derived works.

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  Explanation/Reference:

  Open source software is software that has been released under an Open Source Initiative (OSI) certified license. The definition includes 10 criteria, which are described as follows: Open source software is software that has been released under an Open Source Initiative (OSI) certified license. The definition includes 10 criteria, which are described as follows:

  1.

  Free Redistribution: The license allows any party selling or giving away the software as a component of an aggregate software distribution comprising programs from many different sources.

  2.

  Source code: Anyone can modify the source code.

  3.

  Derived Works: The license must allow changes and derived work under the same conditions as the license of the original software.

  4.

  Integrity of the authors source code: To maintain the integrity of the original authors work, the license may require that changes to the code be provided in patch form.

  5.

  No Discrimination Against Persons or Groups: The license must be nondiscriminatory with respect to persons or group of persons. Therefore, open source license are forbidden from locking anyone out of the process.

  6.

  No Discrimination Against Fields of Endeavor: The license must not restrict anyone from making use of the software in a specific field of endeavor.

  7.

  Distribution of License: The license can be distributed to all but the rights attached to that program must apply to all to whom the program is distributed. And no party can execute any additional license.

  8.

  License Must Not Be Specific to a Product: It may not require that the software be part of particular distribution.

  9.

  License Must Not Restrict Other Software: It may not restrict other non-open source software.

  10.

  License Must Be Technology-Neutral: It may not require the use of technology to apply the license. Answer options B and A are incorrect. These are the characteristics of closed source software.

• Question 149:

  You work as a Network Administrator for McRoberts Inc. The company has a Linux-based network.

  You have created a script named lf.cgi. You want to provide the following permissions on it:

  rwsr-sr-- Which of the following commands will you execute?

  A. chmod 2754
  B. chmod 4754
  C. chmod 6754
  D. chmod 7754
  C. chmod 6754

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  Explanation/Reference:

  According to the question, the permission set requires setting SID with the owner and the group. Moreover, the Read, Write, and Execute permissions on the script file are required for the owner, Read and Execute permissions for the group, and Read permission for others. The chmod command is used to change the permissions. The last three digits, i.e., 754 will provide the required permissions to the owner, group, and others. The digit 7 will provide the Read, Write, and Execute permissions to the owner. The digit 5 will provide the Read and Execute permissions to the group. The digit 4 will provide the Read permission to others. According to the question, you have to set SID for the owner and users. For the owner (SUID), you will have to add 4 as a prefix to the permission number. For the group (SGID), you will have to add 2 as a prefix to it. For setting both the SIDs (SUID and SGID), you will have to add 6 as a prefix to the permission set. Hence, in order to accomplish the task, you will have to run the following command: chmod 6754 This will set the SID for the owner and group on the permission set of the lf.cgi script file. When SID is set, the Execute permission symbol x is replaced with s.

• Question 150:

  Which of the following commands is used to create a tar file?

  A. tar -ivf filename.tar directory/file
  B. tar -cvf filename.tar directory/file
  C. tar -tvf filename.tar
  D. tar -xvf filename.tar
  B. tar -cvf filename.tar directory/file

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  Explanation/Reference:

  The tar -cvf filename.tar directory/file command is used to create a tar file. filename.tar represents the file you are creating and directory/file represents the directory and file you want to put in the archived file.

  Answer option C is incorrect. The tar -tvf filename.tar command is used to list the contents of a tar file.

  Answer option D is incorrect. The tar -xvf filename.tar command is used to extract the contents of a tar file.

  Answer option A is incorrect. There is no such command as tar -ivf filename.tar directory/file.