CV0-003 Reviews Questions

SR-IOV stands for Single Root I/O Virtualization, which is a technology that allows a physical network adapter to be partitioned into multiple virtual functions (VFs) that can be directly assigned to virtual machines (VMs). This way, the network traffic bypasses the software layer of the hypervisor and the virtual switch, and goes directly from the VM to the physical adapter. This reduces the CPU overhead, the network latency, and the packet loss, and improves the network throughput and scalability. SR-IOV can achieve near-native performance for network-intensive applications, such as an integration application that communicates between different application and database servers. By enabling SR-IOV capability on the physical server and the virtual server, the P2V migration can maintain the same level of network throughput and latency as the original physical machine. References: High performance network virtualization with SR-IOV; Supercharge Your Network Throughput via Single Root I/O Virtualization (SR-IOV); Overview of Single Root I/O Virtualization (SR-IOV).

The correct answer is C and D.

C. Fix the file permissions with read-only access to the owner of the file.

D. Open port 22 access for the computer’s public IP address.

The authorized_keys file on the server should have read-only access for the owner of the file, and no access for anyone else. This ensures that only the owner can read the public keys that are authorized to log in, and no one can modify or delete them. The file permissions can be fixed with the command chmod 400 ~/.ssh/authorized_keys on the server. This is a recommended security practice for SSH key-based authentication123.

The computer that wants to log in to the server using SSH key-based authentication needs to have access to port 22 on the server, which is the default port for SSH service. This can be done by opening port 22 access for the computer’s public IP address on the server’s firewall or security group settings. This allows the computer to initiate an SSH connection to the server and authenticate with its private key. Opening port 21, which is used for FTP service, is not relevant or secure for SSH key-based authentication1.

To answer this question, we need to understand the different types of cloud computing models and how they suit the skill sets of the available personnel. According to Google Cloud, there are three main models for cloud computing: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). Each model provides different levels of control, flexibility, and management over the cloud resources and services1.

• IaaS: This model provides access to networking features, computers (virtual or on dedicated hardware), and data storage space. It gives the highest level of flexibility and management control over the IT resources and is most similar to existing IT resources that many IT departments and developers are familiar with2.
• PaaS: This model provides a complete cloud platform for developing, running, and managing applications without the cost, complexity, and inflexibility of building and maintaining the underlying infrastructure. It removes the need for organizations to manage the hardware and operating systems and allows them to focus on the deployment and management of their applications2.
• SaaS: This model provides a completed product that is run and managed by the service provider. It does not require any installation, maintenance, or configuration by the customers. It is typically used for end-user applications that are accessed through a web browser or a mobile app2.

Based on these definitions, we can evaluate each option:

• Option A: Run the web servers in PaaS, and run the databases and email in SaaS. This option is not the best match for the skill sets of the available personnel because it does not leverage their expertise in Linux and web-server engineering. Running the web servers in PaaS means that they will have less control and customization over the web server environment and will have to rely on the service provider’s platform features. Running the databases and email in SaaS means that they will not need any database administration or email management skills, but they will also have less flexibility and security over their data and communication.
• Option B: Run the web servers, databases, and email in SaaS. This option is not a good match for the skill sets of the available personnel because it does not utilize their skills at all. Running everything in SaaS means that they will have no control or responsibility over any aspect of their cloud environment and will have to depend entirely on the service provider’s products. This option may be suitable for some small businesses or non-technical users who do not have any IT skills or resources, but not for a company that has skilled Linux and web-server engineers.
• Option C: Run the web servers in IaaS, the databases in PaaS, and the email in SaaS. This option is the best match for the skill sets of the available personnel because it balances their strengths and weaknesses. Running the web servers in IaaS means that they can use their Linux and web-server engineering skills to configure, manage, and optimize their web server infrastructure according to their needs. Running the databases in PaaS means that they can leverage the service provider’s platform features to simplify their database development and administration tasks without having to worry about the underlying hardware and operating systems. Running the email in SaaS means that they can outsource their email services to a reliable and secure service provider without having to invest in or manage their own email infrastructure.
• Option D: Run the web servers, databases, and email in IaaS. This option is not a good match for the skill sets of the available personnel because it puts too much burden on them. Running everything in IaaS means that they will have to handle all aspects of their cloud environment, including networking, computing, storage, security, backup, scaling, patching, etc. This option may be suitable for some large enterprises or highly technical users who have full control and customization over their cloud environment, but not for a company that has only a couple of skilled database administrators and little expertise in managing email services.

Therefore, option C is the correct answer.

Volume-based licensing is a model where the cost of the software is based on the number of licenses purchased1. This model is commonly used for software that is installed on a specific number of devices, such as antivirus software or office productivity suites1. Therefore, the number of machines is the most important factor when considering licensing costs in this model.

References: CompTIA Cloud+ CV0-003 Exam Objectives, Objective 1.2: Given a scenario, compare and contrast various cloud service models ; Cloud+ Exam CV0-003: CompTIA Cloud+ Licensing Models1