A systems administrator is implementing a new service task with systems at startup and needs to execute a script entitled test.sh with the following content: The administrator tries to run the script after making it executable with chmod +x; however, the script will not run. Which of the following should the administrator do to address this issue? (Choose two.)
Correct Answer: B,C
Explanation The administrator should do the following two things to address the issue: Add #!/bin/bash to the top of the script. This is called a shebang line and it tells the system which interpreter to use to execute the script. Without this line, the script will not run properly. The shebang line should be the first line of the script and should start with #! followed by the path to the interpreter. In this case, the interpreter is bash and the path is /bin/bash. The other option (A) is incorrect because the shebang line should be at the top, not the bottom of the script. Create a unit file for the new service in /etc/systemd/system/ with the name helpme.service in the location. This is necessary to register the script as a systemd service and enable it to run at startup. A unit file is a configuration file that defines the properties and behavior of a service, such as the description, dependencies, start and stop commands, and environment variables. The unit file should have the extension .service and should be placed in the /etc/systemd/system/ directory. The other option (E) is incorrect because /etc/init.d is the directory for init scripts, not systemd services. References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 14: Managing Processes and Scheduling Tasks, pages 429-430.
XK0-005 Exam Question 67
A Linux administrator needs to remove software from the server. Which of the following RPM options should be used?
Correct Answer: D
Explanation The RPM option -e should be used to remove software from the server. The rpm command is a tool for managing software packages on RPM-based Linux distributions. The -e option stands for erase and removes the specified package from the system. This is the correct option to use to accomplish the task. The other options are incorrect because they either do not exist (-s or -d) or do not remove software (-q stands for query and displays information about the package). References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 16: Managing Software, page 489.
XK0-005 Exam Question 68
Ann, a security administrator, is performing home directory audits on a Linux server. Ann issues the su Joe command and then issues the Is command. The output displays files that reside in Ann's home directory instead of Joe's. Which of the following represents the command Ann should have issued in order to list Joe's files?
Correct Answer: A
Explanation The su command is used to switch to another user account on Linux systems. The - option makes the shell a login shell, which means that it will read the profile and environment variables of the target user. Without this option, the shell will retain the environment variables of the original user. This can cause confusion when issuing commands that depend on these variables, such as ls, which uses the $HOME variable to determine the home directory. Therefore, Ann should have issued su - Joe to list Joe's files instead of her own. References: [How to Use su Command in Linux with Examples]
XK0-005 Exam Question 69
A Linux systems administrator is troubleshooting an I/O latency on a single CPU server. The administrator runs a top command and receives the following output: %Cpu(s): 0.2 us, 33.1 sy, 0.0 ni, 0.0 id, 52.4 wa, 0.0 hi, 0.2 si, 0.0 st Which of the following is correct based on the output received from the exe-cuted command?
Correct Answer: C
Explanation The server's CPU is spending too much time waiting for data inputs. This can be inferred from the output of the top command, which shows the percentage of CPU time spent in different states. The wa state stands for wait, and it indicates that the CPU is idle while waiting for an I/O operation to complete. In this case, the wa state is 52.4%, which means that more than half of the CPU time is wasted on waiting for data inputs. This can cause a high I/O latency and affect the performance of the server. The other options are not correct based on the output received from the executed command. The server's CPU is not taking too long to process users' requests, because the us state, which stands for user, is only 0.2%, which means that the CPU is barely used by user processes. The server's CPU does not show a high idle-time value, because the id state, which stands for idle, is 0.0%, which means that the CPU is not idle at all. The server's CPU value for the time spent on system processes is not low, because the sy state, which stands for system, is 33.1%, which means that the CPU is heavily used by system processes. References: How to Use the Linux top Command (and Understand Its Output); [Understanding Linux CPU Load - when should you be worried?]
XK0-005 Exam Question 70
A systems administrator is encountering performance issues. The administrator runs 3 commands with the following output The Linux server has the following system properties CPU: 4 vCPU Memory: 50GB Which of the following accurately describes this situation?
Correct Answer: A
Explanation Based on the output of the image sent by the user, the system is under CPU pressure and will require additional vCPUs. The output shows that there are four processes running upload.sh scripts that are consuming a high percentage of CPU time (99.7%, 99.6%, 99.5%, and 99.4%). The output also shows that the system has only 4 vCPUs, which means that each process is using almost one entire vCPU. This indicates that the system is struggling to handle the CPU load and may experience performance issues or slowdowns. Adding more vCPUs to the system would help to alleviate the CPU pressure and improve the system performance. The system has not been running for over a year, as the uptime command shows that it has been up for only 1 day, 2 hours, and 13 minutes. The number of users logged in to the system is not relevant to the performance issue, as they are not consuming significant CPU resources. The system does not require more memory, as the free command shows that it has plenty of available memory (49 GB total, 48 GB free). References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 15: Managing Memory and Process Execution, pages 468-469.
