LFCS Practice Test 2 — 10 Questions

Question 1

A developer accidentally deleted a critical file /var/log/app.log. The system administrator knows that the file was recently backed up using a cron job that runs 'tar -czf /backup/logs.tar.gz /var/log/'. Which command should the administrator use to restore the file from the backup without extracting the entire archive?

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

tar -xzf /backup/logs.tar.gz --to-stdout var/log/app.log > /var/log/app.log. `tar -xzf` extracts the specified file (`var/log/app.log`) from the compressed archive and `--to-stdout` sends its content to standard output, which is then redirected to recreate the file at `/var/log/app.log`. This restores the single file without extracting the entire archive, matching the requirement precisely.

Answer

tar -xf /backup/logs.tar.gz var/log/app.log

Answer

tar -tf /backup/logs.tar.gz | grep app.log

Answer

cp /backup/logs.tar.gz:/var/log/app.log /var/log/app.log

Question 2

A system administrator is managing a RHEL 8 server that requires a static IP address on interface ens192. The administrator modifies /etc/sysconfig/network-scripts/ifcfg-ens192 to set BOOTPROTO=static, IPADDR=192.168.1.100, PREFIX=24, GATEWAY=192.168.1.1, and DNS1=8.8.8.8. After saving, the administrator runs 'systemctl restart NetworkManager'. The interface obtains the correct static IP and network connectivity works. However, after a reboot of the server, the interface fails to come up with the static IP and instead obtains an IP via DHCP from the local network. The administrator verifies that the DHCP server is active and that the physical connection is good. What is the most likely cause of the issue?

Accepted Answer

The ONBOOT parameter is set to no or missing in the configuration file.. The ONBOOT parameter controls whether the interface is activated at system boot. If set to 'no' or missing entirely, NetworkManager will not bring up the interface automatically after a reboot, causing it to fall back to DHCP if a DHCP client is active. Setting BOOTPROTO=static and IPADDR correctly only takes effect when ONBOOT=yes is present.

Answer

The kernel parameter nomodeset is set in /etc/default/grub.

Answer

The firewall is blocking the static IP assignment.

Answer

The network service is not enabled to start at boot.

Question 3

A system administrator needs to stop a misbehaving process gracefully, allowing it to clean up resources. The process is unresponsive to the standard SIGTERM signal. What should the administrator do next?

Accepted Answer

Use 'kill -15' again, wait a few seconds, then use 'kill -9' if still unresponsive.. The standard escalation path for terminating an unresponsive process is to first send SIGTERM (signal 15) to request a graceful shutdown, then after a brief wait, send SIGKILL (signal 9) if the process has not terminated. This allows the process a chance to clean up resources before being forcibly killed, which is the recommended practice in Linux process management.

Answer

Wait for the process to finish on its own.

Answer

Use 'kill -9' immediately.

Answer

Send SIGTERM again with a higher priority.

Question 4

An administrator wants to run a script daily at 2 AM. They create a timer unit and a service unit. The service unit uses Type=oneshot. Which of the following timer configurations is correct?

Accepted Answer

OnCalendar=*-*-* 02:00:00. `OnCalendar=*-*-* 02:00:00` specifies an absolute calendar event that triggers the timer at 2:00 AM every day, regardless of when the system booted or when the service last ran. This matches the requirement to run a script daily at a fixed time, and it works correctly with a `Type=oneshot` service unit.

Answer

OnUnitActiveSec=24h

Answer

OnBootSec=1d

Answer

OnActiveSec=24h

Question 5

Which THREE of the following are valid methods to temporarily switch to a different user account without logging out entirely? (Choose three.)

Accepted Answer

sudo -u username -s. Options A, B, and E are correct. `sudo -u username -s` launches a shell as the specified user. `su - username` starts a login shell as that user. `runuser -l username -c 'bash'` runs a command as another user (common in scripts). Option C (`newgrp groupname`) changes the group, not the user. Option D (`login username`) requires a full login, which logs out the current session.

Answer

newgrp groupname

Answer

login username

Question 6

A system administrator needs to find all files in /home that are owned by user 'alice' and have been modified in the last 7 days. The administrator then wants to compress those files into a single archive named alice_recent.tar.gz. Which of the following commands accomplishes this?

Accepted Answer

tar -czf alice_recent.tar.gz -T <(find /home -user alice -mtime -7). It uses `tar -czf` with process substitution to compress the files found by `find` into a gzipped tar archive named alice_recent.tar.gz. The `-z` flag enables gzip compression, and `-T <(...)` reads the list of files from the process substitution, which runs `find` to locate files owned by alice modified within the last 7 days. Options A, B, and D either do not compress or use incompatible formats.

Answer

find /home -user alice -mtime -7 -exec tar -rf alice_recent.tar.gz {} +

Answer

find /home -user alice -mtime -7 -print | cpio -o > alice_recent.tar.gz

Answer

find /home -user alice -mtime -7 | tar -cvf alice_recent.tar.gz

Question 7

A system administrator needs to check the firewall rules on a Linux server using firewalld. Which two commands can be used to list the current rules? (Choose two.)

Accepted Answer

firewall-cmd --list-all-zones. `firewall-cmd --list-all-zones` displays the firewall rules for all zones configured in firewalld, showing services, ports, and rules per zone. Option E is correct because `firewall-cmd --list-all` lists the rules for the default zone, providing a concise view of active firewall configuration. Both commands are native to firewalld and directly query its runtime and permanent rules via D-Bus.

Answer

systemctl status firewalld

Answer

iptables -S

Answer

iptables -L

Question 8

Refer to the exhibit. Which filesystem is close to full capacity?

Accepted Answer

/dev/sdb1. The `df -h` output (not shown) indicates that /dev/sdb1 is at 90% capacity, while /dev/sda1 is at 75%. A filesystem at 90% usage is close to full capacity, making D the correct answer. The question tests the ability to read disk usage percentages and identify the one nearing capacity.

Answer

Both are at 75% or less

Answer

/dev/sda1

Answer

Neither

Question 9

Which TWO commands can be used to display the contents of a text file that has been compressed with gzip without decompressing it to disk?

Accepted Answer

zcat file.gz. `zcat` is a standard utility that reads gzip-compressed files and decompresses the output to stdout, allowing you to view the contents without writing a decompressed file to disk. It is functionally equivalent to `gunzip -c` and is commonly used for inspecting compressed log files or text data.

Answer

xzcat file.gz

Answer

gzip -l file.gz

Answer

bzcat file.gz

Question 10

To check the disk usage of the /var/log directory in a human-readable format, which command is appropriate?

Accepted Answer

du -sh /var/log. The `du -sh /var/log` command is correct because `du` (disk usage) estimates file and directory space usage, and the `-s` option summarizes the total for the specified directory, while `-h` prints sizes in human-readable format (e.g., K, M, G). This directly answers the requirement to check disk usage of the /var/log directory in a human-readable form.

Answer

ls -lh /var/log

Answer

df -h /var/log

Answer

fdisk -l /var/log