Linux+ CompTIA Linux+ Security and Access Control 3

Question 1

What is the purpose of the /etc/sudoers file?

Accepted Answer

Defines which users can run commands as other users via sudo

Answer

/etc/sudoers specifies which users or groups are permitted to run commands as root or another user via sudo.

Question 2

Which AppArmor command loads a profile in enforce mode?

Accepted Answer

aa-enforce

Answer

aa-enforce puts an AppArmor profile into enforce mode, actively blocking policy violations.

Question 3

A Linux system uses iptables. Which command saves the current rules so they persist after reboot on a Debian-based system?

Accepted Answer

iptables-save > /etc/iptables/rules.v4

Answer

iptables-save redirects current rules to a file that iptables-persistent reads on boot for rule restoration.

Question 4

Which SSH configuration directive in sshd_config disables password authentication entirely?

Accepted Answer

PasswordAuthentication no

Answer

Setting PasswordAuthentication no in sshd_config forces key-based authentication only, disabling passwords.

Question 5

What does the command 'chattr +i /etc/resolv.conf' accomplish?

Accepted Answer

Sets the file immutable so it cannot be modified or deleted

Answer

chattr +i sets the immutable attribute, preventing any user including root from modifying or deleting the file without first removing the attribute.

Linux Practice Test