CompTIA Updated XK0-006 Exam Questions and Answers by ariyan

This performance-based question tests correct use of the tar utility for backup and restore operations, which is part of System Management in CompTIA Linux+ V8. The key detail is that the backup is explicitly described as uncompressed, so the correct archive file must be a plain .tar file rather than .tar.gz, .tgz, or .tar.bz2.

For the backup command, the correct syntax is:

tar -cvf /backups/application.tar -C /opt/ application

Here, -c creates the archive, -v enables verbose output, and -f specifies the archive filename. The -C /opt/ option changes to the /opt/ directory before archiving, and application is then archived relative to that location. This is the correct Linux+ method because it avoids storing unnecessary leading path components in the archive.

For the restore command, the correct syntax is:

tar -xvf /backups/application.tar -C /opt/

Here, -x extracts the archive, -v displays files being restored, and -f identifies the archive file. The -C /opt/ option ensures the archived application directory is restored back into /opt/, recreating /opt/application correctly.

The other file choices such as /backups/application.tar.gz, /backups/application.tgz, and /backups/application.tar.bz2 are incorrect because they indicate compressed backups, which the question specifically rules out. Likewise, options such as -xzvf or -xjvf are used for gzip- or bzip2-compressed archives and would not apply here.

Therefore, the verified correct PBQ answers are:

Backup: tar -cvf /backups/application.tar -C /opt/ application

Restore: tar -xvf /backups/application.tar -C /opt/

The use of AI-assisted tools for Infrastructure as Code (IaC) is increasingly common in modern DevOps practices, which are covered in the Automation and Orchestration domain of CompTIA Linux+ V8. While AI can accelerate code generation, Linux+ emphasizes that generated code must still follow best practices for quality, security, and maintainability.

Option C, linting generated code, is the correct answer. Linting involves analyzing code for syntax errors, style violations, logical issues, and potential security risks before deployment. When AI tools generate IaC artifacts such as Terraform files, Ansible playbooks, or shell scripts, linting ensures that the output adheres to organizational standards and does not introduce misconfigurations or vulnerabilities.

Linux+ V8 documentation stresses that automation does not eliminate the need for validation. Administrators remain responsible for verifying correctness and compliance. Linting tools such as ansible-lint, terraform fmt, and shell linters help detect issues early in the pipeline and prevent faulty infrastructure deployments.

The other options are poor practices. Copying and pasting code increases the risk of errors and inconsistency. Generating monolithic code contradicts modular IaC principles. Merging CI/CD pipelines is unrelated to validating AI-generated infrastructure code.

Therefore, the correct answer is C. Linting generated code.

Pluggable Authentication Modules (PAM) provide a flexible, centralized mechanism for managing authentication across various services in a Linux system. According to the CompTIA Linux+ V8 security domain, protecting against " dictionary attacks " and " brute-force " attempts is a critical hardening step. A dictionary attack involves an automated script attempting thousands of common passwords against a user account.

To mitigate this, administrators use pam_tally2 (or the newer pam_faillock on some systems). The pam_tally2 module is specifically designed to keep track of failed login attempts for each user. It can be configured in the PAM stack (such as /etc/pam.d/common-auth or /etc/pam.d/password-auth) to lock an account after a specified number of consecutive failed attempts (e.g., deny=5). Once the threshold is reached, the user is blocked from further attempts for a set period or until an administrator manually resets the counter. This effectively stops automated dictionary attacks from continuing indefinitely.

The other options serve different purposes. pam_limits (Option B) is used to set resource limits (like CPU time or number of open files) for users once they are already logged in. pam_unix (Option C) is the standard module for traditional /etc/passwd and /etc/shadow authentication. pam_ldap (Option D) allows the system to authenticate against a remote LDAP directory.

While these modules are part of the PAM ecosystem, only pam_tally2 is designed for tracking and acting upon failed login counts to block attacks.

To create an appropriate device label, format and create an ext4 file system on the new partition, you can use the following commands:

To create a GPT (GUID Partition Table) label on the new drive /dev/sdc, you can use the parted command with the -s option (for script mode), the device name (/dev/sdc), the mklabel command, and the label type (gpt). The command is:

parted -s /dev/sdc mklabel gpt

To create a primary partition of 10 GB on the new drive /dev/sdc, you can use the parted command with the -s option, the device name (/dev/sdc), the mkpart command, the partition type (primary), the file system type (ext4), and the start and end points of the partition (1 and 10G). The command is:

parted -s /dev/sdc mkpart primary ext4 1 10G

To format and create an ext4 file system on the new partition /dev/sdc1, you can use the mkfs command with the file system type (ext4) and the device name (/dev/sdc1). The command is:

mkfs.ext4 /dev/sdc1

You can verify that the new partition and file system have been created by using the lsblk command, which will list all block devices and their properties.