EX200 Essential Tools Practice Test 4 — 15 Questions

Question 1

Refer to the exhibit. Why did the sshd service fail?

Accepted Answer

The service start was requested too many times in quick succession.. B is correct because systemd's `StartLimitIntervalSec` and `StartLimitBurst` settings (default: 10 seconds and 5 starts) prevent rapid service restarts. When `sshd` fails repeatedly within the interval, systemd marks it as failed with the status 'start-limit-hit' to avoid resource exhaustion from restart loops.

Answer

The service binary is missing.

Answer

The configuration file /etc/ssh/sshd_config has a syntax error.

Answer

The system ran out of memory.

Question 2

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

Accepted Answer

The script is not executable.. The cron job fails because the script lacks execute permissions. Cron requires that scripts specified in crontab entries have the executable bit set (chmod +x) for the user under whose crontab the job runs. Without this, the cron daemon cannot spawn the script as a process, resulting in errors.

Answer

The script is owned by root.

Answer

The cron daemon is not running.

Answer

The script uses absolute paths.

Question 3

A system administrator needs to view the last 10 lines of the log file /var/log/messages in real time as new lines are added. Which command should be used?

Accepted Answer

tail -f /var/log/messages. The `tail -f /var/log/messages` command displays the last 10 lines of the file by default and then continues to output new lines as they are appended, providing real-time monitoring. The `-f` (follow) option keeps the file open and polls for changes, making it the correct tool for live log watching.

Answer

less /var/log/messages

Answer

head -n 10 /var/log/messages

Answer

cat /var/log/messages

Question 4

A system administrator runs the command 'ls -l' and sees that a file has permissions '-rwxr-xr-x'. The administrator wants to remove execute permission for the group and others while keeping it for the owner. Which chmod command should be used?

Accepted Answer

chmod go-x file. Option C is correct because the command 'chmod go-x file' removes execute permission for group (g) and others (o) while leaving the owner's permissions unchanged. The current permissions '-rwxr-xr-x' indicate owner has rwx, group has r-x, and others have r-x, so removing execute from group and others yields '-rwxr--r--'.

Answer

chmod u-x file

Answer

chmod 755 file

Answer

chmod a+x file

Question 5

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?

Accepted Answer

find /var -type f -size +100M -mtime -7 -exec du -h {} + | sort -rh. Option C is correct because it uses `find` with `-size +100M` and `-mtime -7` to match files larger than 100MB modified within 7 days, then `-exec du -h {} +` aggregates sizes in human-readable format, and `sort -rh` sorts by the first field (size) in reverse human-numeric order, producing the required descending list.

Answer

find /var -type f -size +100M -mtime -7 -ls | sort -k7 -n

Answer

find /var -type f -size +100M -mtime -7 -exec ls -lh {} \; | sort -k5 -h

Answer

find /var -type f -size +100M -mtime -7 -printf '%s %p
' | sort -n -r | head -20

Question 6

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?

Accepted Answer

Run 'nohup command &' before logout. Option A is correct because `nohup` ignores the SIGHUP signal that the shell sends to its child processes when the parent shell exits (e.g., upon logout). By running `nohup command &`, the command is placed in the background and will continue running even after the SSH session terminates, as it is immune to the hangup signal.

Answer

Run 'command', press Ctrl+Z, then type 'bg' and logout

Answer

Run 'command &' and then exit

Answer

Run 'command & disown' then logout

Question 7

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?

Accepted Answer

pidof apache2; renice -n 19 -p . Option B is correct because `pidof apache2` retrieves the PID of the apache2 process, and `renice -n 19 -p ` sets the priority to the lowest possible (least favorable) scheduling value. In Linux, `renice` accepts nice values from -20 (highest priority) to 19 (lowest priority), so 19 is the correct value for the least favorable scheduling.

Answer

pidof apache2; renice -n 20 -p <PID>

Answer

ps -C apache2 -o pid=; renice -n -20 -p <PID>

Answer

ps aux | grep apache2; nice -n 19 <PID>

Question 8

A company policy requires that all cron jobs run by non-root users must be logged to a specific file /var/log/usercron.log. The system administrator decides to use rsyslog to capture these messages. Which configuration directive should be added to /etc/rsyslog.conf or a file in /etc/rsyslog.d/ to achieve this?

Accepted Answer

cron.* /var/log/usercron.log. Option B is correct because the cron facility in rsyslog captures messages generated by the cron daemon, including cron jobs run by non-root users. By adding the directive `cron.* /var/log/usercron.log` to the rsyslog configuration, all cron messages (regardless of priority) are logged to the specified file, satisfying the policy requirement.

Answer

user.* /var/log/usercron.log

Answer

*.* /var/log/usercron.log

Answer

authpriv.* /var/log/usercron.log

Question 9

A user wants to set an environment variable named 'EDITOR' to the value '/usr/bin/vim' so that it is available in all future login sessions. Which file should the user add the export command to?

Accepted Answer

~/.bash_profile. The ~/.bash_profile file is executed for login shells, making it the correct place to set environment variables like EDITOR that should persist across all future login sessions. Adding 'export EDITOR=/usr/bin/vim' to this file ensures the variable is defined each time the user logs in.

Answer

~/.bash_logout

Answer

/etc/bashrc

Answer

~/.bashrc

Question 10

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?

Accepted Answer

tar -czvf archive.tar.gz --exclude='*.tmp' /path/to/dir. Option A is correct because it uses `tar -czvf` to create a gzip-compressed archive with maximum compression (the `z` flag invokes gzip, which by default uses level 6; for maximum compression you would add `--gzip --level=9` or use `GZIP=-9`, but the question's 'maximum compression' is a common phrasing for gzip). The `--exclude='*.tmp'` option is placed before the source directory, which is the correct syntax for tar to apply the exclusion pattern to all files during archiving. This command compresses the directory into a single `.tar.gz` file while omitting all temporary files.

Answer

tar -czvf archive.tar.gz /path/to/dir --exclude='*.tmp'

Answer

tar -cjvf archive.tar.bz2 --exclude='*.tmp' /path/to/dir

Answer

tar -czvf archive.tar.gz /path/to/dir

Question 11

A system administrator wants to monitor all files in /var/log that are currently being written to by processes. Which command shows file descriptors that are open for writing by any process?

Accepted Answer

lsof +D /var/log | grep -E '(REG|DIR).*[0-9]+[w]'. Option B is correct because `lsof +D /var/log` lists all open file descriptors under the /var/log directory recursively, and the `grep` pattern `(REG|DIR).*[0-9]+[w]` filters for regular files or directories with a write file descriptor (the 'w' in the file descriptor mode column). This directly shows which files are currently being written to by any process.

Answer

inotifywait -m /var/log

Answer

fuser -v /var/log

Answer

lsof /var/log

Question 12

Which TWO commands can be used to view the contents of a compressed file named 'data.log.gz' without decompressing it permanently? (Choose exactly two.)

Accepted Answer

zcat data.log.gz. B is correct because `zcat` reads the contents of a gzip-compressed file and outputs them to standard output without permanently decompressing the file. It is functionally equivalent to `gunzip -c` and is the standard tool for viewing compressed text files in place.

Answer

gunzip data.log.gz

Answer

gzip -d data.log.gz

Answer

bzcat data.log.gz

Question 13

Which THREE of the following are valid methods to schedule a recurring task in Red Hat Enterprise Linux 8? (Choose exactly three.)

Accepted Answer

Creating a systemd timer unit. Systemd timer units are the modern, recommended method for scheduling recurring tasks in RHEL 8. They replace traditional cron-based scheduling by leveraging systemd's service and timer units, providing features like monotonic timers, calendar events, and integration with systemd's logging and dependency management.

Answer

Using the 'batch' command

Answer

Using the 'at' command

Question 14

Which TWO of the following are valid examples of using redirection and pipes in bash to append the output of a command to a file while also displaying it on the terminal? (Choose exactly two.)

Accepted Answer

command | tee -a file. Option B is correct because `tee -a file` reads from stdin and writes both to stdout and appends to the named file. The pipe `|` sends the stdout of `command` to `tee`, so the output is displayed on the terminal and appended to `file`. The `-a` flag ensures append mode, not overwrite.

Answer

command 2>&1 | tee file

Answer

command > file

Answer

command >> file

Question 15

Refer to the exhibit. An administrator runs these commands on a server. The administrator suspects a performance issue. Which observation from the exhibit is most likely causing a bottleneck?

Accepted Answer

The 'create' directive requires root privileges, but the job runs as appuser.. Option D is correct because the `create` directive in logrotate requires root privileges to create new log files with the specified ownership and permissions. Since the job runs as `appuser`, it lacks the necessary privileges to execute the `create` directive, causing the rotation to fail and potentially leading to a bottleneck as logs are not rotated properly.

Answer

The 'notifempty' directive may cause delays in rotation.

Answer

The 'compress' directive uses bzip2 by default, which is not installed.

Answer

The 'weekly' directive uses cron syntax incorrectly.

EX200 Essential Tools Practice Test 4 — 15 Questions

Exhibit

EX200 Essential Tools Practice Test 4 — 15 Questions

Exhibit