XK0-006 System Management Practice Test 5 — 15 Questions

Question 1

A Linux administrator needs to identify which of the following filesystems are journaling filesystems commonly used in Linux. (Choose three.)

Accepted Answer

ext4. ext4, xfs, and btrfs are journaling filesystems. FAT32 is not journaling. swap is a swap space, not a filesystem.

Answer

swap

Answer

FAT32

Question 2

A user has a file with permissions set to 644. Which of the following commands will add the setuid permission to the file? (Choose two.)

Accepted Answer

chmod u+s file. chmod u+s file adds setuid via symbolic. chmod 4644 file sets permissions to rwsr--r-- (setuid). The other options: chmod 2644 sets SGID; chmod 1644 sets sticky bit; chmod g+s sets SGID.

Answer

chmod g+s file

Answer

chmod 1644 file

Answer

chmod 2644 file

Question 3

Which of the following commands can be used to display the contents of a file one page at a time? (Choose two.)

Accepted Answer

less. The `less` command is a pager that displays file contents one screen at a time, allowing both forward and backward navigation. It is designed for viewing large files interactively, loading only the visible portion into memory for efficiency.

Answer

head

Answer

cat

Answer

tail

Question 4

A Linux administrator needs to locate all files in /var/log that were modified more than 7 days ago. Which command should be used?

Accepted Answer

find /var/log -mtime +7. The find command with -mtime +7 finds files modified more than 7 days ago. locate uses a database and does not support -mtime; grep is for text search; ls does not filter by modification time.

Answer

grep -mtime +7 /var/log

Answer

ls -mtime +7 /var/log

Answer

locate -mtime +7 /var/log

Question 5

A user wants to create a hard link named 'linkfile' to an existing file 'original'. Which command accomplishes this?

Accepted Answer

ln original linkfile. The ln command without -s creates a hard link. ln -s creates a symbolic link. cp copies the file; mv moves it.

Answer

mv original linkfile

Answer

ln -s original linkfile

Answer

cp original linkfile

Question 6

An administrator notices that a service named 'httpd' is not running. They want to check its current status and, if inactive, start it. Which set of systemctl commands should be used?

Accepted Answer

systemctl status httpd; if inactive, systemctl start httpd. systemctl status httpd shows the status; if inactive, systemctl start httpd starts it. The other options have incorrect commands or syntax.

Answer

systemctl list-units httpd; if inactive, systemctl run httpd

Answer

systemctl show httpd; if inactive, systemctl launch httpd

Answer

systemctl is-active httpd; if inactive, systemctl enable httpd

Question 7

A file has permissions set to 2755. Which special permission is enabled, and what does it do?

Accepted Answer

SGID; new files in the directory inherit the group. The permission 2755 includes the SGID (Set Group ID) special permission, indicated by the leading digit '2'. When SGID is set on a directory, new files and subdirectories created within it inherit the group ownership of the directory, rather than the primary group of the user who creates them. This is critical for collaborative environments where multiple users need shared group access.

Answer

No special permission; it is just octal 755

Answer

Sticky bit; only file owners can delete their files

Answer

SUID; the file runs with the owner's privileges

Question 8

Which command displays the amount of free and used disk space on all mounted file systems in a human-readable format?

Accepted Answer

df -h. df -h shows disk space in human-readable units. du shows disk usage per directory; lsblk lists block devices; mount shows mounted filesystems but not space usage.

Answer

du -h /

Answer

lsblk -h

Answer

mount -h

Question 9

An administrator wants to change the default systemd target to multi-user.target so the system boots to a text console. Which command should be used?

Accepted Answer

systemctl set-default multi-user.target. systemctl set-default multi-user.target sets the default target. systemctl isolate changes the current target but not the default. enable and mask are for services, not targets.

Answer

systemctl isolate multi-user.target

Answer

systemctl enable multi-user.target

Answer

systemctl mask multi-user.target

Question 10

A technician needs to search a log file for lines containing either 'ERROR' or 'FATAL' and display the line numbers. Which command accomplishes this?

Accepted Answer

grep -n -E 'ERROR|FATAL' logfile. grep -n -E 'ERROR|FATAL' logfile uses extended regex with alternation and -n for line numbers. -i ignores case, but the stem does not mention case-insensitive; -v inverts match; -r is recursive.

Answer

grep -v -E 'ERROR|FATAL' logfile

Answer

grep -r -n 'ERROR|FATAL' logfile

Answer

grep -i 'ERROR|FATAL' logfile

Question 11

A system administrator runs 'umask 027' in a Bash shell. What will be the default permissions for a new directory created in that shell? (Assume no other umask changes.)

Accepted Answer

rwxr-x--- (750). The umask value 027 subtracts permissions from the base 777 for directories. 777 minus 027 equals 750, which translates to rwxr-x---. The owner gets full permissions (rwx), the group gets read and execute (r-x), and others get no permissions (---).

Answer

rwxrwxr-x (775)

Answer

rwxrwxrwx (777)

Answer

rw-rw-r-- (664)

Question 12

After making changes to /etc/grub.d/ and /etc/default/grub, an administrator needs to regenerate the GRUB2 configuration file. Which command should be used?

Accepted Answer

grub2-mkconfig -o /boot/grub2/grub.cfg. After modifying /etc/grub.d/ scripts or /etc/default/grub, the GRUB2 configuration file must be regenerated to apply the changes. The command `grub2-mkconfig -o /boot/grub2/grub.cfg` reads the configuration snippets and defaults, then writes the final boot menu configuration to the specified output file. This is the standard method on RHEL/CentOS 7+ and other distributions using GRUB2.

Answer

grub2-install

Answer

grub2-set-default 0

Answer

update-grub

Question 13

A process is consuming excessive CPU and needs to be terminated immediately. The PID is 1234. Which command will terminate the process with the most forceful signal?

Accepted Answer

kill -9 1234. kill -9 (SIGKILL) forcibly terminates the process. SIGTERM (15) is graceful; SIGHUP (1) reloads config; SIGSTOP (19) suspends.

Answer

kill -15 1234

Answer

kill -1 1234

Answer

kill -19 1234

Question 14

An administrator wants to display only the second field from a colon-delimited file named 'passwd' using a text processing tool. Which command will achieve this?

Accepted Answer

awk -F: '{print $2}' passwd. awk -F: '{print $2}' passwd sets field separator to : and prints second field. cut -d: -f2 also works, but the options include awk. sed is for editing, not field extraction; grep is for pattern matching.

Answer

sed 's/:.*//' passwd

Answer

cut -d: -f2 passwd

Answer

grep -o '^[^:]*:[^:]*' passwd

Question 15

Which directory in the Filesystem Hierarchy Standard (FHS) contains essential user commands available to all users, such as 'ls' and 'cp'?

Accepted Answer

/bin. /bin contains essential user binaries. /sbin is for system binaries (usually root). /usr/bin contains non-essential user binaries. /opt is for optional software.

Answer

/sbin

Answer

/opt

Answer

/usr/bin