RHCSA Essential Command-Line Tools Questions and Answers

Question 1

A system administrator needs to find all files within the `/etc` directory that are owned by the `root` user and have been modified in the last 7 days. Which command will accomplish this?

Accepted Answer

find /etc -user root -mtime -7

Answer

find /etc -user root -mtime +7

Answer

find /etc -group root -mmin -7

Answer

find /etc -user root -ctime 7

Question 2

Which of the following commands correctly creates a bzip2-compressed tar archive named `backup.tar.bz2` containing the contents of the `/home/user/data` directory?

Accepted Answer

tar -cjf backup.tar.bz2 /home/user/data

Answer

tar -czf backup.tar.bz2 /home/user/data

Answer

tar -xjf backup.tar.bz2 /home/user/data

Answer

tar -cvf backup.tar.bz2 /home/user/data

Question 3

A system administrator needs to search through `/var/log/messages` for lines containing the exact word 'error', but not 'errors' or 'error-code'. Which command should be used?

Accepted Answer

grep -w 'error' /var/log/messages

Answer

grep 'error' /var/log/messages

Answer

grep -v 'error' /var/log/messages

Answer

grep -i 'errors' /var/log/messages

Question 4

An application with PID 2501 is completely unresponsive. The administrator first tried `kill 2501`, but the process did not terminate. What is the most appropriate next command to forcefully stop the process?

Accepted Answer

kill -9 2501

Answer

kill -1 2501

Answer

kill -15 2501

Answer

killall -9 application_name

Question 5

To perform an in-place replacement of every occurrence of the IP address `10.0.1.50` with `10.0.2.50` within the file `/etc/config.txt`, which `sed` command should be used?

Accepted Answer

sed -i 's/10.0.1.50/10.0.2.50/g' /etc/config.txt

Answer

sed 's/10.0.1.50/10.0.2.50/' /etc/config.txt > /etc/config.txt

Answer

sed 's/10.0.1.50/10.0.2.50/g' /etc/config.txt

Answer

sed -i 's/10.0.1.50/10.0.2.50/' /etc/config.txt

Question 6

A user account named `testuser` exists. A system administrator needs to add this user to the `wheel` supplementary group and also change their login shell to `/usr/bin/zsh`. Which of the following commands accomplishes both tasks in a single operation?

Accepted Answer

usermod -aG wheel -s /usr/bin/zsh testuser

Answer

usermod -G wheel -s /usr/bin/zsh testuser

Answer

useradd -aG wheel -s /usr/bin/zsh testuser

Answer

groupmod -a wheel testuser && usermod -s /usr/bin/zsh testuser