Essential Tools

A developer needs to search for the string 'ERROR' in all files under /var/log, but wants to exclude files ending with '.gz'. Which command is correct?

Which TWO commands can be used to display the current date and time in a format like '2023-10-05 14:30:00'?

During boot, a server fails to mount an NFS filesystem listed in /etc/fstab. Which troubleshooting step should be taken first to isolate the issue?

A script needs to be run at system boot for a specific user. Which method ensures the script runs with that user's environment?

Refer to the exhibit. What does the file permission -rw------- indicate about /etc/shadow?

Refer to the exhibit. The backup script runs every 5 minutes but generates errors. What is the most likely cause?

A system administrator wants to find all files in /var that are larger than 100MB and have been modified within the last 7 days. The output should be a list of file paths with sizes in human-readable format, sorted by size descending. Which command pipeline accomplishes this?

A user wants to run a command in the background after logging out of an SSH session. Which method ensures the process continues even after logout?

An administrator receives an alert that a process named 'apache2' is consuming excessive CPU. The administrator needs to identify the PID of the process and then change its priority to the lowest possible value (least favorable scheduling). Which sequence of commands should be used?

An administrator needs to compress a directory containing subdirectories and files into a single archive file, with maximum compression, and exclude all '*.tmp' files. Which command should be used?

A system administrator has created a new group named 'ops'. The administrator wants to add the existing user 'alice' to this group as a supplementary group without affecting her current group memberships. Which command should be used?

An administrator needs to schedule a script to run every Monday, Wednesday, and Friday at 2:30 PM. Which cron expression should be used?

A Red Hat Enterprise Linux server has been configured with a custom repository for offline updates. The administrator runs 'yum repolist' and the custom repository is not listed. Which command should be used to verify that the repository configuration file is valid and located in the correct directory?

An administrator notices that the /tmp directory is filling up quickly. They want to find all files in /tmp that are larger than 100 MB and owned by user 'ftp', then delete them. The administrator runs: find /tmp -type f -size 100M -user ftp -exec rm {} \;. However, this command deletes only files that are exactly 100 MB, not larger. Which find expression should be used instead?

A system administrator notices that a server is responding slowly. The administrator runs `top` and sees a process named `backup_script` consuming 95% CPU. The process runs as root and is supposed to run nightly backups. However, the system load average is low. The administrator wants to investigate without killing the process. Which of the following is the best course of action?