XK0-005 Exam Dumps - CompTIA Linux+ Exam

Part 1

Here is the step-by-step command construction process:

1. Move the private key (likely named server1 based on the provided details) to the .ssh directory:

mv ~/server1 ~/.ssh/id_rsa

This command moves the private key (assuming it's named server1) from the home directory (~) to the .ssh directory and renames it to id_rsa (which is the default SSH private key file name).

2. Set the correct permissions for the private key file:

chmod 600 ~/.ssh/id_rsa

The private key file should be readable and writable only by the owner to maintain security.

3. Connect to the server using the private key and the correct port (2222):

ssh -i ~/.ssh/id_rsa -p 2222 admin@server1

This command tells ssh to use the specified private key (-i ~/.ssh/id_rsa), connect on port 2222 (-p 2222), and log in as the admin user on server1.

Part 2: Setting File Permissions

The correct command to set the file permissions based on the screenshots would likely involve using chmod. Here is the command to set permissions correctly:

chmod 600 ~/.ssh/id_rsa

This restricts the private key's permissions so that only the user can read and write it.

Part 3: Setting Ownership

If ownership needs to be set, the command would look like this:

chown comptia:comptia ~/.ssh/id_rsa

This command ensures that the file is owned by the correct user (comptia) and the correct group (comptia).

In part 4, it asks you to select the proper file for editing to enable remote server access. Based on standard SSH configuration requirements, the proper file to edit for remote server access would be ~/.ssh/config.

Here’s why:

~/.ssh/config: This file allows you to set up configuration options for different hosts, including specifying ports, user names, and the identity file (private key). You would add the necessary configuration for server1 to this file for easier access.

Other options:

~/.ssh/authorized_keys: This file lists public keys that are authorized to log in to the local system. It's not meant for configuring remote access to another server.

~/.ssh/known_hosts: This file stores the host keys of servers you’ve connected to. It doesn’t allow for editing remote access settings.

~/.ssh/server1: This seems like a private key file or another custom file, but it’s not typically used to configure SSH options.

For configuring access to server1 on port 2222, you would add a block like this to the ~/.ssh/config file:

Host server1

HostName server1

Port 2222

User admin

IdentityFile ~/.ssh/id_rsa

The script in option B performs the task by SSH-ing into each server listed in serverslist and then adding each user listed in userslist. This is an effective way to remotely create user accounts without manually logging into each server. The ssh command allows the execution of the useradd commands on the remote machines.

The interface enp1s0 is bound to the public zone, but HTTP and HTTPS are allowed in the internal zone only. The services must be added to the active zone for the correct interface.

Source: CompTIA Linux+ XK0-005 Study Guide – Chapter 12: Network Security

The dig command uses the DNS servers listed in the /etc/resolv.conf file to resolve domain names. If the dig command returns an NXDOMAIN response, it means the domain does not exist according to the DNS servers used. Therefore, the administrator should check the /etc/resolv.conf file first34.

The iptables command is used to configure firewall rules in Linux.To allow packets from a specific source (192.168.10.22) to the server, we must append a rule to the INPUT chain:

iptables -A INPUT -s 192.168.10.22 -j ACCEPT

Explanation of the command:

-A INPUT → Appends a rule to the INPUT chain (incoming traffic).

-s 192.168.10.22 → Specifies the source IP address.

-j ACCEPT → Accepts the packet and allows communication.

Why the other options are incorrect?

A. iptables -L -s 192.168.10.22 -j ACCEPT → Incorrect, -L is used to list rules, not to add them.

B. iptables -D INPUT -s 192.168.10.22 -j ACCEPT → Incorrect, -D is used to delete a rule, not add one.

D. iptables -A OUTPUT -S 192.168.10.22 -j ACCEPT → Incorrect, -A OUTPUT affects outgoing packets, but we need to accept incoming packets.

Persisting the Rule:

To make the rule persistent after a reboot, it must be saved:

iptables-save > /etc/iptables/rules.v4

The presence of a static entry in /etc/hosts for www.comptia.org forces the system to use this IP address instead of querying DNS.

This prevents proper IPv6 (AAAA) resolution, as /etc/hosts only contains an IPv4 (A) record.

Removing this static entry allows the system to query DNS for both IPv4 and IPv6 records.

Comprehensive and Detailed Step-by-Step Explanation:

The apt update command updates the package lists for repositories but does not upgrade installed packages.

After apt update, the administrator should run apt upgrade to install the latest versions of all packages.

rpm --update is incorrect because RPM does not have an --update option for updating repositories. RPM package management requires yum or dnf on RHEL-based systems.

dnt update is not a valid command (probably a typo for dnf update, which would be used on Fedora/RHEL systems).

dpkg --update is incorrect because dpkg is used for managing individual .deb packages and does not update repositories.

This will prevent the file app.conf from being tracked by Git and uploaded to the repository. The .gitignore file is a special file that contains patterns of files and directories that Git should ignore. Any file that matches a pattern in the .gitignore file will not be staged, committed, or pushed to the remote repository. The .gitignore file should be placed in the root directory of the repository and committed along with the other files.

The other options are incorrect because:

A. Run git exclude app.conf

This is not a valid Git command. There is no such thing as git exclude. The closest thing is git update-index --assume-unchanged, which tells Git to temporarily ignore changes to a file, but it does not prevent the file from being uploaded to the repository.

B. Run git stash app.conf

This will temporarily save the changes to the file app.conf in a stash, which is a hidden storage area for uncommitted changes. However, this does not prevent the file from being tracked by Git or uploaded to the repository. The file will still be part of the working tree and the index, and it will be restored when the stash is popped or applied.

C. Add app.conf to .exclude

This will have no effect, because Git does not recognize a file named .exclude. The only files that Git uses to ignore files are .gitignore, $GIT_DIR/info/exclude, and core.excludesFile.