Cloud Infrastructure & Operation

UNIX is an open source operating system. Open source refers to a type of software that allows users to view, modify, and distribute the source code. This means that anyone can access and modify the underlying code of UNIX, making it highly customizable and adaptable to different needs. As an operating system, UNIX provides a platform for running software and managing computer hardware resources. It is known for its stability, security, and scalability, making it a popular choice for servers and high-performance computing environments.

The kernel is considered the main portion or heart of LINUX because it is the core component that interacts directly with the hardware and manages system resources. It provides essential services such as process management, memory management, device drivers, and file system access. The kernel is responsible for maintaining the stability, security, and overall functioning of the operating system. Without the kernel, LINUX would not be able to function properly.

FaaS stands for Function as a Service, which is a cloud computing model where developers can execute individual functions in the cloud without managing the infrastructure. It allows developers to focus solely on writing and deploying code, without worrying about servers or scaling. Therefore, FaaS is indeed a cloud service model, making it the incorrect answer for this question.

The correct answer is "esc + :wq". In the vi editor, pressing the escape key (esc) allows the user to enter command mode. The ":wq" command in vi stands for "write and quit", which saves the changes made to the file and exits the editor. Therefore, pressing escape followed by ":wq" allows the user to save and exit the vi editor.

The correct answer is "rmdir". This command is used to remove or delete a directory in a file system. It is specifically designed for deleting directories and will only work if the directory is empty. If the directory contains any files or subdirectories, the command will not work and an error message will be displayed. Therefore, "rmdir" is the appropriate command to delete a directory.

In vi editor, the keystroke "esc + dd" allows the user to delete one line of words. The "esc" key is used to switch from insert mode to command mode, and the "dd" command is used to delete the current line. So, pressing "esc" followed by "dd" will delete the line the cursor is currently on.

The command "chmod 764 test2.txt" is the correct answer because it changes the permission access of "test2.txt" to -rwxrw-r--. In the chmod command, the first digit represents the owner's permission, the second digit represents the group's permission, and the third digit represents the others' permission. In this case, the owner has read, write, and execute permissions (7), the group has read and write permissions (6), and others have read-only permission (4).

The statement "LINUX is cheap" is not an advantage of LINUX because although LINUX is an open-source operating system and can be obtained for free, the cost associated with implementing and maintaining a LINUX system can still be significant. This includes expenses related to hardware, software, training, and technical support. Therefore, while LINUX may be cost-effective compared to some proprietary operating systems, it is not necessarily cheap in all aspects.

The SUDO program allows users to access root privileges on a system. This means that users can execute commands and perform tasks that are typically restricted to the system administrator. By using SUDO, users can temporarily elevate their privileges and perform administrative tasks without having to log in as the root user. This helps to enhance security and limit the potential damage that can be caused by unauthorized access to system resources.

A community cloud deployment model is used when there is a need for sharing data, platform, and applications among a specific group with a common goal. In a community cloud, multiple organizations or individuals with similar interests or requirements come together to share resources and collaborate on projects. This model allows for cost-sharing, increased security, and customized solutions tailored to the specific needs of the community members.

The correct answer is "-rw-rw-r--". In this symbol, the first character "-" represents a regular file, the next three characters "rw-" represent the owner's permission as read and write, the next three characters "rw-" represent the group's permission as read and write, and the last three characters "r--" represent the guest's permission as read only.

Orchestrator is the correct answer because it is a tool used to automate the creation, monitoring, and deployment of resources in a data center. It helps in managing and coordinating various tasks and workflows, allowing for efficient and streamlined operations. OVF (Open Virtualization Format) is a standard for packaging and distributing virtual machines, but it does not specifically focus on automation or resource management. Service Manager is a tool for managing and automating IT service delivery, but it may not have the same level of focus on data center resources as Orchestrator. Virtual Machine Manager is a tool for managing virtual machines, but it may not cover the broader range of data center resource automation that Orchestrator does.

The directory /dev/hdb is described as a "Hard disk (slave)". This indicates that it is a secondary hard disk drive connected to the computer. In a master-slave configuration, the primary hard disk is the master, and the secondary hard disk is the slave. The slave drive typically has a lower priority and is used for additional storage or backup purposes.

To achieve a secure connection between a Private Cloud and a Public Cloud provider, the environment can be connected through a Virtual Private Network (VPN). A VPN creates a secure and encrypted connection between the two networks, ensuring that data transmitted between them is protected from unauthorized access. By establishing a VPN connection, organizations can securely transfer data and communicate between their Private Cloud and the Public Cloud provider, minimizing the risk of data breaches and ensuring the confidentiality and integrity of their information.

A strong encryption service based on cryptography can effectively prevent mapping attacks. Mapping attacks involve gathering information about a network or system to identify vulnerabilities and potential points of entry. By encrypting the data, it becomes extremely difficult for attackers to decipher and gain insights into the network or system's structure and weaknesses. This ensures that even if attackers manage to intercept the encrypted data, they will not be able to extract any valuable information from it. Therefore, a strong encryption service based on cryptography is the best defense against mapping attacks.

The correct answer is "tell LINUX that the file is to be executed by bin/bash". This is because the first line in the script "#!/bin/bash" is known as the shebang, and it specifies the interpreter to be used to execute the script, which in this case is the bash shell.

A private cloud deployment model is the solution if there is a need for a high degree of governance. In a private cloud, the infrastructure is dedicated to a single organization, providing them with full control over security, compliance, and data governance. This allows the organization to implement strict governance policies and ensure that their sensitive data and resources are protected. Compared to public or hybrid clouds, a private cloud offers a higher level of control and customization, making it suitable for organizations with specific governance requirements.

Hijacking is the correct answer because it refers to a type of attack where an unauthorized person intercepts and takes control of a communication session between two parties. This attacker can monitor and manipulate the communication without the knowledge of the communicating parties. Hijacking can occur in various forms, such as session hijacking or man-in-the-middle attacks, where the attacker can eavesdrop on the communication, alter the data being transmitted, or even impersonate one of the parties involved.

The file "/etc/nologin" is classified under the system administration category because it is used to prevent users from logging into the system. When this file exists, it displays a message to users attempting to log in and denies them access. This file is commonly used during system maintenance or when the administrator wants to restrict user access temporarily.

SOA stands for Service Oriented Architecture. It is a design approach that organizes software components as services, which can be accessed and reused by different applications. This architecture promotes loose coupling, flexibility, and interoperability between systems. It allows businesses to integrate and combine various software components and services to create new applications or modify existing ones easily.

Device Denial-of-Service Attacks is not a form of DoS attack. A DoS attack is designed to overwhelm or disrupt the normal functioning of a network, system, or device. Buffer Overflow Attacks, SYN floods, and Smurf Attacks are all examples of DoS attacks. However, Device Denial-of-Service Attacks refers to attacks that target specific devices, such as routers or switches, rather than the entire network or system. These attacks aim to exhaust the resources of the targeted device, causing it to become unresponsive or unavailable.

The bin sub-directory in Linux contains programs that correspond to core Linux commands. These programs are essential for the functioning of the Linux system and are used for various tasks and operations. The bin directory is typically included in the system's PATH variable, allowing users to easily access these core commands from any directory in the system.

Automated updates are not a limitation of cloud computing because they are actually a benefit. Cloud computing allows for automatic updates to be applied to software and systems, ensuring that users always have the latest features and security patches without needing to manually install them. This helps to improve efficiency and reduce the risk of security vulnerabilities. Therefore, automated updates are not a limitation, but rather a valuable feature of cloud computing.

A 16 ports SAN switch with a single controller component is classified as a Modular Class. This means that the switch has a modular design, allowing for expansion and customization by adding additional modules or components as needed. The single controller component indicates that there is only one controller managing the switch's operations.

The Access Layer is not a SAN component layer. In a Storage Area Network (SAN), the Access Layer refers to the layer that provides connectivity between the SAN fabric and the servers or hosts. It includes components such as host bus adapters (HBAs) and network switches. The Host Layer, Fabric Layer, and Storage Layer are all valid SAN component layers. The Host Layer consists of the servers or hosts that access the SAN. The Fabric Layer includes the network switches and other devices that form the SAN fabric. The Storage Layer refers to the storage devices, such as disk arrays or tape libraries, that store the data in the SAN.