XK0-006 System Management Practice Test 6 — 15 Questions

Question 1

A Linux administrator needs to view real-time information about running processes, including CPU and memory usage. Which TWO commands can be used for this purpose? (Choose two.)

Accepted Answer

top. top and htop provide real-time process information with CPU/memory usage. ps gives a snapshot; kill is for terminating; systemctl manages services.

Answer

ps aux

Answer

systemctl list-units

Answer

kill -l

Question 2

A technician is troubleshooting a service that fails to start. The service file is located in /usr/lib/systemd/system. Which THREE commands can be used to investigate the service's status and logs? (Choose three.)

Accepted Answer

journalctl -u servicename. systemctl status shows service status; journalctl -u shows logs for the unit; journalctl -f follows new log entries. systemctl start attempts to start but not investigate; systemctl enable enables at boot.

Answer

systemctl enable servicename

Answer

systemctl start servicename

Question 3

A Linux administrator needs to change the permissions of a file to be readable and writable by the owner, readable by the group, and no access for others. Which command accomplishes this?

Accepted Answer

chmod 640 file. The octal representation 640 sets owner read/write (6), group read (4), and others none (0).

Answer

chmod 600 file

Answer

chmod 664 file

Answer

chmod 644 file

Question 4

A system administrator wants to find all files in /var/log that have been modified in the last 7 days and are larger than 100MB. Which command should be used?

Accepted Answer

find /var/log -mtime -7 -size +100M. The -mtime -7 finds files modified within 7 days, -size +100M finds files larger than 100MB.

Answer

find /var/log -mtime +7 -size +100M

Answer

find /var/log -atime -7 -size +100M

Answer

find /var/log -mtime -7 -size -100M

Question 5

A developer wants to grant a user named 'john' read and write permissions to a file, but the file currently has an ACL that gives 'jane' full control. The administrator wants to add an ACL entry for 'john' without modifying existing entries. Which command accomplishes this?

Accepted Answer

setfacl -m u:john:rw file. setfacl -m adds or modifies an ACL entry without affecting others.

Answer

setfacl -x u:john:rw file

Answer

setfacl -b u:john:rw file

Answer

chmod u+rw file; setfacl -m u:john:rw file

Question 6

Which of the following commands will display the last 10 lines of a log file and also output new lines as they are appended?

Accepted Answer

tail -f logfile. The `tail -f logfile` command displays the last 10 lines of the file by default and then continues to monitor the file for new lines, outputting them as they are appended. The `-f` (follow) option keeps the file open and polls for changes, making it the standard tool for real-time log monitoring.

Answer

head -f logfile

Answer

less +F logfile

Answer

cat logfile

Question 7

A user wants to run a command that will continue running even after the user logs out. Which command should be used?

Accepted Answer

nohup command &. nohup makes the command immune to hangups and runs in the background.

Answer

disown command

Answer

command &

Answer

bg command

Question 8

Which directory in the FHS contains essential user command binaries that are needed in single-user mode?

Accepted Answer

/bin. The /bin directory, as defined by the Filesystem Hierarchy Standard (FHS), contains essential user command binaries (e.g., ls, cp, mv) that are required for booting, repairing, and operating the system in single-user mode. Single-user mode mounts only the root filesystem, so /bin must be on the root partition to provide these critical utilities without relying on other filesystems like /usr.

Answer

/usr/bin

Answer

/sbin

Answer

/opt/bin

Question 9

An administrator needs to permanently mount an ext4 filesystem on /dev/sdb1 to the /data directory. Which file must be edited to ensure the mount persists across reboots?

Accepted Answer

/etc/fstab. /etc/fstab contains filesystem mount points and options that are automatically mounted at boot.

Answer

/etc/sysconfig/network

Answer

/etc/default/grub

Answer

/etc/mtab

Question 10

A system running systemd is failing to boot properly. The administrator wants to boot into an environment with only the essential services for troubleshooting. Which systemd target should be selected at boot?

Accepted Answer

rescue.target. rescue.target starts a minimal system with root filesystem mounted read-only and basic services.

Answer

multi-user.target

Answer

emergency.target

Answer

graphical.target

Question 11

Which command is used to query the status of a service managed by systemd?

Accepted Answer

systemctl status servicename. systemctl status shows whether a service is active, enabled, and recent log entries.

Answer

journalctl -u servicename

Answer

service servicename status

Answer

systemctl list-units --type=service

Question 12

An administrator wants to change the priority of a running process with PID 1234 to a lower priority (nicer). The current nice value is 0. Which command will set the nice value to 10?

Accepted Answer

renice 10 -p 1234. The `renice` command is used to alter the scheduling priority of an already running process. By default, a process starts with a nice value of 0. Running `renice 10 -p 1234` sets the nice value to 10, which is a lower priority (more 'nice') because the kernel adds this value to the dynamic priority calculation, giving the process less CPU time.

Answer

nice -n 10 kill 1234

Answer

chrt -p 10 1234

Answer

kill -10 1234

Question 13

A developer creates a hard link to a file and then deletes the original file. What happens to the hard link?

Accepted Answer

The hard link still contains the data and is accessible.. Hard links share the same inode; deleting the original file removes one link, but the data remains accessible via the hard link until all links are removed.

Answer

The hard link is broken and cannot be accessed.

Answer

The hard link is automatically converted to a copy of the file.

Answer

The hard link becomes a symbolic link.

Question 14

Which command will display the disk usage of each directory in the current directory, in human-readable format?

Accepted Answer

du -h. The `du -h` command displays disk usage for each directory in the current directory, with the `-h` flag converting sizes into human-readable formats (e.g., K, M, G). This is the correct tool for per-directory disk usage reporting.

Answer

fdisk -l

Answer

ls -lh

Answer

df -h

Question 15

A system administrator needs to remove all files in /tmp that have not been accessed in the last 30 days and are not owned by root. Which two commands, combined, could be used to accomplish this? (Select TWO).

Accepted Answer

find /tmp -atime +30 -not -user root -delete. find with -atime and -not -user root locates files; then use -exec rm or -delete to remove.

Answer

find /tmp -mtime +30 -not -user root -delete

Answer

find /tmp -atime -30 -user root -delete

Answer

find /tmp -atime +30 -user root -exec rm {} \;