linux plus practice test Practice Exam: Test Your Knowledge 2025

A Linux administrator needs to view all currently running processes in a hierarchical tree format showing parent-child relationships. Which command should the administrator use?

A system administrator discovers that a critical service fails to start automatically after a system reboot. The service is managed by systemd. Which command should be used to configure the service to start automatically at boot?

A developer needs to search for all files containing the text string 'database_password' within the /var/www directory and all its subdirectories. Which command accomplishes this task most effectively?

An administrator needs to configure a firewall rule using firewalld to allow incoming HTTPS traffic permanently. Which command should be executed?

A Linux server is experiencing performance issues. An administrator runs the 'top' command and notices that the load average shows 15.3, 12.8, 10.5. The server has 4 CPU cores. What does this indicate?

A company requires a bash script to run automatically every day at 2:30 AM to perform system backups. Which is the most appropriate method to schedule this task?

An administrator needs to change the ownership of all files in /opt/application and its subdirectories to user 'appuser' and group 'appgroup'. Which command accomplishes this correctly?

A web server's error logs show 'Permission denied' errors when attempting to bind to port 80. The service is configured to run as a non-root user 'webuser'. What is the most secure solution to resolve this issue?

A system administrator is troubleshooting a Docker container that fails to start. The error message indicates 'no space left on device'. However, running 'df -h' shows plenty of disk space available. What is the most likely cause?

An organization needs to create a bash script that checks if a service is running and restarts it if it's down. Which script structure correctly implements this logic?

A systems engineer needs to configure persistent kernel parameters for network performance tuning. Which file should be modified to ensure these settings persist across reboots?

An administrator is investigating unauthorized access attempts. Which command provides the most comprehensive view of recent successful and failed login attempts?

A Linux administrator needs to troubleshoot DNS resolution issues. The system should use a specific DNS server at 8.8.8.8. After modifying /etc/resolv.conf with 'nameserver 8.8.8.8', the changes are lost after reboot. What is the most likely cause?

A DevOps engineer is creating a Dockerfile for a web application. The application requires several large dependency packages. Which Dockerfile practice best optimizes image size and build cache efficiency?

A production server is experiencing intermittent hangs. An administrator notices high I/O wait times in the 'top' command output. Which command provides detailed information about which processes are causing disk I/O bottlenecks?

An administrator needs to configure SSH to prevent root login and disable password authentication, allowing only key-based authentication. Which changes should be made to /etc/ssh/sshd_config?

A Linux system administrator needs to create a logical volume that can be expanded later without downtime. The system has a volume group named 'vg_data' with available space. Which sequence of commands creates a 50GB logical volume named 'lv_app' and formats it with ext4?

A containerized application deployed using docker-compose needs to persist database data across container restarts. Which docker-compose.yml configuration correctly implements this requirement?

A server suddenly cannot resolve any hostnames. The administrator confirms network connectivity is working by successfully pinging external IP addresses. Running 'cat /etc/resolv.conf' shows it is empty. The system uses systemd-resolved. What is the correct troubleshooting approach?

An administrator needs to archive and compress the entire /var/log directory while preserving permissions and ownership, then transfer it to a remote server. Which command accomplishes this most efficiently?