LCA User & Permission Management 2

Question 1

Which file stores the encrypted password hashes for local user accounts on a Linux system?

Accepted Answer

/etc/shadow

Answer

/etc/shadow stores hashed passwords and password aging info, readable only by root.

Question 2

What command changes the group ownership of a file named report.txt to the group 'finance'?

Accepted Answer

chown :finance report.txt

Answer

chown :groupname file changes only the group owner of a file.

Question 3

A file has permissions -rwsr-xr-x. What does the 's' in the owner execute position indicate?

Accepted Answer

SUID bit is set

Answer

An 's' replacing the owner execute bit means the SUID bit is set, causing the file to run as its owner.

Question 4

Which command locks a user account by prepending '!' to the password hash in /etc/shadow?

Accepted Answer

usermod -L username

Answer

usermod -L locks an account by inserting '!' before the password hash, preventing password-based login.

Question 5

What octal permission value sets read+write for owner, read-only for group, and no permissions for others?

Accepted Answer

640

Answer

640 = owner rw- (6), group r-- (4), others --- (0).

(LCA) Certified Linux Administrator Practice Test