パスできるXK0-006試験最速合格保証2025問題集！ [Q49-Q74]

パスできるXK0-006試験最速合格保証2025問題集！

XK0-006問題集完全版問題で試験学習ガイド

質問 # 49
While hardening a system, an administrator runs a port scan with Nmap, which returned the following output:

Which of the following is the best way to address this security issue?

A. Configuring a firewall to block traffic on port 23 on the server
B. Closing port 80 on the network switch to block traffic
C. Changing the systems administrator's password to prevent unauthorized access
D. Disabling and removing the Telnet service on the server

正解：D

解説：
Port 23/tcp indicates Telnet, which is insecure because it transmits data in plaintext. The best hardening approach is to disable and remove the Telnet service entirely, eliminating the vulnerability rather than just blocking it at the firewall. Secure alternatives like SSH should be used instead.

質問 # 50
A Linux administrator needs to create and then connect to the app-01-imagecontainer. Which of the following commands accomplishes this task?

A. docker exec -dc app-01-image
B. docker start -td app-01-image
C. docker run -it app-01-image
D. docker build -ic app-01-image

正解：C

解説：
The docker run -it command both creates a new container from the specified image and attaches to it interactively, which is exactly what the administrator needs.

質問 # 51
A Linux administrator is attempting to capture all network traffic coming to the server from the
10.0.6.5 IP address. Which of the following commands should the administrator run on the server to achieve the goal?

A. tcpdump host 10.0.6.5
B. tcpdump net 10.0.6.5
C. tcpdump ip 10.0.6.5
D. tcpdump addr 10.0.6.5

正解：A

解説：
tcpdump host 10.0.6.5applies a Berkeley Packet Filter that matches any packets to or from the IP 10.0.6.5, capturing all traffic involving that host. The netqualifier is for entire subnets, ip isn't a valid filter keyword by itself, and addris not recognized in tcpdump's filter syntax.

質問 # 52
A Linux administrator needs to analyze a compromised disk for traces of malware. To complete the analysis, the administrator wants to make an exact, block-level copy of the disk. Which of the following commands accomplishes this task?

A. cp -rp /dev/sdc/* /tmp/image
B. cpio -i /dev/sdc -ov /tmp/image
C. tar cvzf /tmp/image /dev/sdc
D. dd if=/dev/sdc of=/tmp/image bs=8192

正解：D

解説：
The dd command performs a low-level, block-by-block copy of a device. Using if=/dev/sdc (input file) and of=/tmp/image (output file) with a block size (bs) ensures an exact replica of the disk, suitable for forensic analysis.

質問 # 53
A systems administrator is creating a backup copy of the /home/directory. Which of the following commands allows the administrator to archive and compress the directory at the same time?

A. tar -cJf /backups/home.tar.xz /home/
B. dd of=/backups/home.tar.xz if=/home/
C. cpio -o /backups/home.tar.xz /home/
D. rsync -z /backups/home.tar.xz /home/

正解：A

解説：
The tar -cJf command creates (-c) an archive, compresses it with XZ (-J), and writes it to a file (- f). This allows archiving and compression of the /home/ directory in one step.

質問 # 54
Which of the following describes the method of consolidating system events to a single location?

A. Webhooks
B. Threshold monitoring
C. Health checks
D. Log aggregation

正解：D

解説：
Log aggregation is the process of collecting and consolidating logs from multiple sources into a single location, making it easier to analyze and manage system events.

質問 # 55
A systems administrator is preparing a Linux system for application setup. The administrator needs to create an environment variable with a persistent value in one of the user accounts.
Which of the following commands should the administrator use for this task?

A. export VAR=value
B. echo "export VAR=value" >> ~/.bashrc
C. VAR=value
D. export "VAR=$VAR:value" >> ~/.ssh/profile

正解：B

解説：
Adding export VAR=value to ~/.bashrc ensures the environment variable is set persistently for the user. The variable will load automatically in every new shell session.

質問 # 56
A systems administrator receives reports about connection issues to a secure web server. Given the following firewall and web server outputs:

Which of the following commands best resolves this issue?

A. ufw disable
B. ufw allow 80/tcp
C. ufw allow 4096/tcp
D. ufw delete deny https/tcp

正解：D

解説：
The firewall output shows that port 443/tcp (HTTPS) is explicitly denied, even though the web server is correctly listening on it. Removing the deny rule for HTTPS (ufw delete deny https/tcp) resolves the issue while still keeping the firewall active and secure.

質問 # 57
A systems administrator is working on an SFTP server configuration. Which of the following commands will best enable the connectivity to that service from the 10.10.0.0/24 network?

A. sudo ufw allow from 10.10.0.0/24 to any port 22
B. sudo ufw allow 0:22/tcp from 10.10.0.0
C. sudo ufw allow in on eth0 to any port 22
D. sudo ufw allow from 10.10.0.0/24

正解：A

解説：
The command sudo ufw allow from 10.10.0.0/24to any port 22 explicitly opens TCP port 22 (used by SFTP/SSH) only for hosts in the 10.10.0.0/24 network.

質問 # 58
Which of the following cryptographic functions ensures a hard drive is encrypted when not in use?

A. LUKS
B. OpenSSL
C. GPG
D. PKI certificates

正解：A

解説：
LUKS (Linux Unified Key Setup) provides full-disk encryption, ensuring that the data on a hard drive is protected and unreadable when the system is powered off or the drive is not in use.

質問 # 59
Which of the following commands should an administrator use to convert a KVM disk file to a different format?

A. qemu-img
B. qemu-kvm
C. qemu-ng
D. qemu-io

正解：A

解説：
The qemu-img command is used to create, convert, and manage disk image files for KVM/QEMU. It allows conversion between formats such as qcow2, raw, and vmdk.

質問 # 60
A Linux systems administrator needs to extract the contents of a file named
/home/dev/web.bkpto the /var/www/html/directory. Which of the following commands should the administrator use?

A. unzip -c /home/dev/web.bkp /var/www/html/
B. cd /var/www/html/ && gzip -c /home/dev/web.bkp | tar xf -
C. pushd /var/www/html/ $$ cpio -idv < /home/dev/web.bkp && popd
D. tar -c -f /home/dev/web.bkp /var/www/html/

正解：C

解説：
The .bkp file here is a cpio archive, not a tar or zip. The correct way to extract it is by changing into the target directory (/var/www/html/) and using cpio -idv < /home/dev/web.bkp. The pushd and popd commands ensure the administrator returns to the original directory afterward.

質問 # 61
An administrator must secure an account for a user who is going on extended leave. Which of the following steps should the administrator take? (Choose two).

A. Instruct the user to log in once per week.
B. Change the user's shell to /sbin/nologin.
C. Set the user's files to immutable.
D. Delete the user's /homefolder.
E. Run the command passwd -l user.
F. Change the date on the /homefolder to that of the expected return date.

正解：B、E

解説：
passwd -l user locks the user's account by disabling the password, preventing logins.
Change the user's shell to /sbin/nologin ensures the account cannot be used for interactive logins, further securing it.

質問 # 62
Users connecting to a MySQL database on a Linux system report frequent errors. An administrator reviews the following partial output of the /proc/meminfo and freecommands:

Which of the following should the administrator do to ensure that the MySQL service will continue to run even if the system runs out of swap space? (Choose two.)

A. Use disk quotas on the swap space to prevent MySQL from overutilizing the swap partition.
B. Issue the dd if=/dev/zero of=/swapfile bs=1024 count=65536 command.
C. Issue the mkswap /dev/sda2; swapon -v /dev/sda2 command.
D. Issue the sysctl -w vm.overcommit_ratio=100 command.
E. Reload the /etc/fstab file by issuing the mount -a command.(Not sufficient alone)
F. Issue the sysctl -w vm.overconunit_memory=2 command.(Invalid key)

正解：B、C

解説：
Creating a swap file with dd if=/dev/zero of=/swapfile bs=1024 count=65536 allocates additional swap space that MySQL can use when RAM is exhausted.
Formatting and enabling a swap partition with mkswap /dev/sda2; swapon -v /dev/sda2 brings another swap device online, further increasing the system's swap capacity.

質問 # 63
A Linux server is not starting up because files in the /boot/partition are corrupt. After the initial GRUB screen, the following message is displayed:
Probing EDD (edd=off to disable)... ok
uncompression error
--system halted
Which of the following steps should the Linux administrator take to recover the system without destroying the existing installation? (Choose two.)

A. Start up the system using rescue boot media.
B. Increase the amount of swap memory.
C. Replace the hard drive.
D. Reinstall the OS.
E. Start up in single-user mode.
F. Reinstall the kernel packages.

正解：A、F

解説：
Using rescue boot media lets you boot the machine, mount the existing partitions, and access the corrupted /boot files without reinstalling the OS.
Reinstalling the kernel packages restores the missing or corrupt files in /boot (e.g., vmlinuz and initramfs), allowing GRUB to load and uncompress the kernel properly.

質問 # 64
A systems administrator manages multiple Linux servers and needs to set up a reliable and secure way to handle the complexity of managing event records on the OS and application levels.
Which of the following should the administrator do?

A. Implement a centralized log aggregation solution.
B. Deploy log rotation procedures to manage the records.
C. Create an automated process to retrieve logs from the server by demand.
D. Configure daily automatic backups of logs to remote storage.

正解：A

解説：
A centralized log aggregation solution (such as Elasticsearch, Graylog, or Splunk) provides reliable and secure management of logs across multiple servers. It consolidates OS and application logs, simplifies analysis, and improves monitoring and security compared to on- demand retrieval, backups, or simple log rotation.

質問 # 65
An average of one out of three users in a company cannot reach the company website. A Linux administrator determines that one of the three website servers is down. The administrator inspects the DNS configuration for the website and notices the following entry:

Which of the following accurately explains the issue?

A. The administrator has incorrectly configured the DNS server to be an iterative resolver instead of an authoritative resolver.
B. DNS returns all three records in a different order each time, and the browser typically uses the first address in the DNS response.
C. One of the DNS records has not been signed with a DNSSEC-supported key, and this is causing some web browsers to reject the DNS response.
D. The DNS configuration is missing corresponding AAAA records and PTR records, and this is causing clients to fail the hostname translation.

正解：B

解説：
With multiple A records, DNS performs simple round-robin ordering and returns the records in a different sequence on each query. Most clients try the first address returned-so when the downed server's IP appears first (about one in three times), those users cannot connect.

質問 # 66
A Linux administrator needs to create and then connect to the app-01-imagecontainer. Which of the following commands accomplishes this task?

A. docker exec -dc app-01-image
B. docker start -td app-01-image
C. docker run -it app-01-image
D. docker build -ic app-01-image

正解：C

解説：
The docker run -it command both creates a new container from the specified image and attaches to it interactively, which is exactly what the administrator needs.

質問 # 67
Which of the following most accurately describes a webhook?

A. An SNMP-based API for network device monitoring
B. An HTTP-based callback function
C. An authentication method for web-server communication
D. A means to transmit sensitive information between systems

正解：B

解説：
A webhook is an HTTP-based callback that allows one system to send real-time data or notifications to another system when an event occurs.

質問 # 68
Which of the following describes PEP 8?

A. The style guide for Python code
B. Python virtual environments
C. A package installer for Python
D. A Python variable holding octal values

正解：A

解説：
PEP 8 is the official Python Enhancement Proposal that provides coding style guidelines for writing clean, consistent, and readable Python code.

質問 # 69
Which of the following commands should an administrator use to see a full hardware inventory of a Linux system?

A. dmesg
B. lscpu
C. dmidecode
D. lsmod

正解：C

解説：
dmidecode retrieves detailed hardware information from the system's DMI/SMBIOS, including BIOS, CPU, memory, and motherboard details, providing a full hardware inventory.

質問 # 70
Following the completion of monthly server patching, a Linux administrator receives reports that a critical application is not functioning. Which of the following commands should help the administrator determine which packages were installed?

A. dnf info
B. dnf search
C. dnf list
D. dnf history

正解：D

解説：
The dnf history command shows a log of past package operations (install, update, remove), allowing the administrator to review which packages were installed or updated during the patching process.

質問 # 71
To perform a live migration, which of the following must match on both host servers? (Choose two).

A. USB ports
B. Disk storage path
C. Available memory
D. CPU architecture
E. Available swap
F. Network speed

正解：B、D

解説：
CPU architecture must match because live migration requires CPU compatibility to continue running the virtual machine without errors.
Disk storage path must match so the migrated VM can access its virtual disks seamlessly on the destination host.

質問 # 72
After system startup, the X Window System GUI login interface is not displaying. Which of the following commands ensures that the GUI is started during the system startup process?

A. systemctl enable xwindow.service
B. systemctl set-default graphical.target
C. systemctl unmask xwindow.service
D. systemctl isolate graphical.target

正解：B

解説：
Setting the default target to graphical.targettells systemd to boot into the graphical interface on startup. The command systemctl set-default graphical.targetmakes the GUI login display automatically at boot.

質問 # 73
SIMULATION 3
You are a systems administrator and have created an uncompressed backup of the application directory. Several hours later, you must restore the application from backup.
INSTRUCTIONS
Within each tab, click on an object to form the appropriate command used to create the backup and restore the application.
Command objects may only be used once, but the spacebar ˽ object may be used multiple times.
Not all objects will be used. Click the arrow to remove any unwanted objects from your command.
If at any time you would like to bring back the initial state of the simulation, please click the Reset All button.

正解：

解説：

-cvf creates (-c) a verbose (-v) archive file (-f) named /backups/application.tar.
-C /opt/ application changes to /opt/ so only the relative application directory is saved, avoiding absolute paths.
-xvf extracts (-x) the same archive, and -C /opt/ restores the contents back into the original location.