Virtualization Concepts and Hypervisor Functions
53 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is the primary function of a hypervisor in a virtualized environment?

  • To monitor network traffic between VMs
  • To increase the speed of physical server operations
  • To eliminate the need for physical servers
  • To manage and allocate resources to virtual machines (correct)

    • How does a virtual machine perceive its environment in relation to hardware resources?

  • It is aware of shared resources with other VMs
  • It uses virtualization layers to enhance performance
  • It directly accesses the hardware without interference
  • It believes it has exclusive access to physical resources (correct)

    • What mechanism does the hypervisor use to allocate processor and memory resources to VMs?

  • Prioritization depending on the VM type
  • Round-robin scheduling method (correct)
  • Static allocation determined at boot
  • Dynamic scaling based on application load

    • Which of the following is NOT a benefit of using VMs compared to traditional processes?

    <p>Direct control over the full hardware stack (A)</p> Signup and view all the answers

    What percentage of hardware utilization can be achieved in a virtualization environment, as mentioned?

    <p>55% (D)</p> Signup and view all the answers

    Which statement accurately describes the role of the Virtual Machine Monitor (VMM)?

    <p>It is responsible for creating and managing VMs alongside the hypervisor (B)</p> Signup and view all the answers

    In a virtualized environment, how do VMs ensure they do not disrupt each other?

    <p>Through the hypervisor's management and isolation features (B)</p> Signup and view all the answers

    What is the illusion experienced by each operating system running on a VM?

    <p>It perceives exclusive access to the host's resources (A)</p> Signup and view all the answers

    What is one advantage of using VMM over traditional operating systems?

    <p>VMM provides higher security verification ease. (C)</p> Signup and view all the answers

    How does system-level virtualization manage CPU resources?

    <p>By multiplexing the underlying CPU among multiple VMs. (C)</p> Signup and view all the answers

    What is one of the considerations when using virtual machines?

    <p>Different VMs can have different software requirements. (B)</p> Signup and view all the answers

    What is a key characteristic of VMM compared to an OS?

    <p>VMM is a simpler component than an operating system. (A)</p> Signup and view all the answers

    What does the term 'machine switch' refer to in the context of VMM?

    <p>The step of saving the state of a VM before running another. (B)</p> Signup and view all the answers

    What was one consequence of poor isolation in server environments during the 1980s and 1990s?

    <p>An application crash could affect the whole server (D)</p> Signup and view all the answers

    Which factor contributed to the stagnation of virtualization during the emergence of personal computers?

    <p>The focus on single-user applications (D)</p> Signup and view all the answers

    What was a significant change in server architecture during the late 1990s to early 2000s?

    <p>High volume manufacturing changed servers from custom-built to general-purpose processors (A)</p> Signup and view all the answers

    In the context of the year 2000 pre-virtualization scenario, what was the average hardware utilization across different operating systems?

    <p>12-18% (A)</p> Signup and view all the answers

    What purpose did virtualization serve as a solution to in the early 2000s?

    <p>To improve isolation between applications (B)</p> Signup and view all the answers

    Why was sharing resources less emphasized with the emergence of the PC?

    <p>Cheap hardware made individual ownership more common. (B)</p> Signup and view all the answers

    What was a key characteristic of application behavior in server environments before virtualization?

    <p>Multiple applications shared the same operating system. (D)</p> Signup and view all the answers

    Which of the following statements best describes the primary shift in server operations due to virtualization?

    <p>Multiple operating systems could coexist on a single physical machine. (D)</p> Signup and view all the answers

    What is fault tolerance?

    <p>The capability of a system to function correctly despite component failures. (D)</p> Signup and view all the answers

    What occurs when a fault is not addressed properly?

    <p>Failure (B)</p> Signup and view all the answers

    Which of the following correctly describes a fault?

    <p>A defect or imperfection that has the potential to cause issues. (C)</p> Signup and view all the answers

    Which redundancy approach provides multiple layers of backup to enhance fault tolerance?

    <p>Massive redundancy (C)</p> Signup and view all the answers

    In the context of fault tolerance, what is the result of an error?

    <p>An indication of a fault. (C)</p> Signup and view all the answers

    What is the primary challenge in developing reliable computer systems?

    <p>Addressing the fact that components can and will fail. (B)</p> Signup and view all the answers

    Which of the following describes the relationship between a subsystem failure and fault perspective?

    <p>A failure in a subsystem is a fault from the perspective of the larger subsystem. (A)</p> Signup and view all the answers

    What happens when a fault is addressed properly?

    <p>It ensures continued smooth operation without disruptions. (C)</p> Signup and view all the answers

    What is a key benefit of using cloud computing in terms of financial management?

    <p>Converts Capital Expenses to Operational Expenses (C)</p> Signup and view all the answers

    In what way does the public cloud environment typically benefit its users?

    <p>Ensures users pay only for what they actually use (A)</p> Signup and view all the answers

    Which deployment model combines on-premises, private cloud, and public cloud services?

    <p>Hybrid Cloud (C)</p> Signup and view all the answers

    What is a characteristic of private cloud environments?

    <p>Dedicated infrastructure with exclusive control (C)</p> Signup and view all the answers

    Which of the following service models specifically provides storage solutions?

    <p>StaaS (B)</p> Signup and view all the answers

    How does the economy of scale benefit cloud computing users?

    <p>By reducing prices through shared infrastructure (B)</p> Signup and view all the answers

    What is a primary advantage of elastic infrastructure in cloud computing?

    <p>It can be scaled according to demand (C)</p> Signup and view all the answers

    Which of the following statements accurately describes the functionality of cloud computing as defined by NIST?

    <p>It provides convenient and on-demand network access to shared resources (B)</p> Signup and view all the answers

    What is a potential drawback of using a private cloud compared to public cloud services?

    <p>Higher upfront investment and maintenance costs (D)</p> Signup and view all the answers

    What does multi-tenancy in cloud computing imply?

    <p>Infrastructure is shared among multiple users (A)</p> Signup and view all the answers

    Which cloud service model typically provides consumers with complete applications?

    <p>SaaS (D)</p> Signup and view all the answers

    What is one of the major reasons companies favor hybrid cloud solutions?

    <p>They allow complete control over data privacy and compliance (A)</p> Signup and view all the answers

    Which statement is true regarding the service model known as FaaS?

    <p>It relates to event-driven execution of functions in the cloud (B)</p> Signup and view all the answers

    What does 'go global fast and easy' imply about cloud computing's business benefits?

    <p>Ability to leverage a worldwide network of resources (A)</p> Signup and view all the answers

    Which of the following services best exemplifies a cloud service?

    <p>Uber or Lyft services (C)</p> Signup and view all the answers

    What does PUE stand for in the context of data centers?

    <p>Power Usage Effectiveness (D)</p> Signup and view all the answers

    Which value of PUE indicates a very efficient data center?

    <p>1.1 (B)</p> Signup and view all the answers

    Which of the following factors is NOT a consideration for data center operations?

    <p>Low installation costs (C)</p> Signup and view all the answers

    What is the primary advantage of using Infrastructure as a Service (IaaS)?

    <p>No need for server maintenance (A)</p> Signup and view all the answers

    Which aspect significantly influences data center efficiency?

    <p>Heat dissipation methods (A)</p> Signup and view all the answers

    Which of the following services is classified as Platform as a Service (PaaS)?

    <p>Integrated development environments (IDEs) (C)</p> Signup and view all the answers

    What does carbon intensity measure in the context of energy usage?

    <p>Emitted greenhouse gases per kWh (C)</p> Signup and view all the answers

    A critical characteristic of Software as a Service (SaaS) is:

    <p>Access through a standard web browser (D)</p> Signup and view all the answers

    Which company operates the Mesa Data Center known for its large size?

    <p>Apple (D)</p> Signup and view all the answers

    Study Notes

    Cloud Computing (Part I)

    • The presentation was given by Rodrigo Bruno
    • Covered the topic of Cloud Computing, part I
    • Also touched on the concept of Virtual Machines

    Recap (Protocols)

    • Presented a diagram illustrating the layered network protocols
    • FIRE (7, "Lucifer", evade) protocols appear at the top and bottom layers

    Recap (Routing)

    • Depicts a network diagram with computers, networks, gateways, switches, and a router
    • Computers have unique IP addresses (e.g., 192.168.1.7, 10.80.7.8)
    • Network 1 and Network 2 are connected by a router
    • Network gateways have IP addresses (e.g., 192.168.1.1, 10.80.7.1)

    Recap (OSI Layers)

    • Explains the functionalities and responsibilities of each OSI layer
    • TCP (Reliable communication) and IP (Multi-network communication) are mentioned
    • Application, Presentation, Session, Transport, Network, Data Link, and Physical layers are described

    Recap (Internet)

    • Showcases how data flow through routers via hops
    • Individual routers have unique IP addresses (e.g., 171.64.10.1, 173.255.219.1)
    • Diagrams demonstrates different routers on an internet path, including Nick's machine with IP addres (171.64.64.166) and a destination on codingbat.com with IP address (173.255.219.70)

    Possible Code Contents

    • Presentation included a cartoon-style diagram illustrating common coding problems
    • Problems like TODO's, hidden bugs, duplicate code, complexity, missing features, etc. were highlighted

    Mainframe Virtualization (early days)

    • Diagram showing logical VMs on a mainframe
    • Shows multiple VMs (VM #1, VM #2, VM #3, etc.) sharing resources on a physical mainframe

    Stagnation of Virtualization (1980s-1990s)

    • PC emergence reduced sharing needs due to cheap hardware
    • Single-user applications dominated servers
    • Server hardware was often custom-built
    • Poor application isolation led to system-wide crashes

    Infrastructures in the late 1990s - early 2000s

    • Shows a diagram of many servers
    • Each server runs a single application (e.g., File Server, Web Server, DNS Server, App Server, Domain Server)

    Pre-virtualization scenario (circa 2000)

    • The diagram illustrates many servers each running a single application with low resource utilization
    • Only 12% to 18% of hardware is being utilized

    Solution: virtualization!

    • One physical server hosts multiple virtual machines (VMs)
    • Each VM operates its own operating system & applications
    • A hypervisor controls the physical server, and allows different VMs to safely share the same server

    Post-virtualization scenario

    • Significantly higher hardware utilization (55%) after implementing virtualization, compared to the earlier scenarios
    • Applications still run on their own operating systems in VMs
    • The hypervisor manages the VMs in a efficient way

    Hypervisor scheduling

    • The hypervisor manages CPU, memory, and resources among VMs.
    • VMs are processed using a round-robin process.
    • The hypervisor prevents virtual machines from interfering with one another

    Hypervisor types

    • Type-1 (bare metal) hypervisor directly communicates with the hardware. Xen, VMware ESX/ESXi, Hyper-V are examples.
    • Type-2 hypervisor runs on top of a host OS and are often used for VMs on personal computers, like VMware Workstation, VirtualBox, KVM.

    Why VMs instead of more processes?

    • VM isolation is easier compared to multiple processes on a single OS sharing resources.
    • Better security due to not sharing file system
    • Isolation improves performance

    Consolidation by virtualization

    • Virtualization improves hardware utilization & efficiency
    • Reducing energy consumption due to server consolidation

    System-level virtualization

    • The physical machine acts as a switch for the VMs, similar to an operating system managing processes on a CPU.
    • It's a way to improve performance & efficient hardware utilization
    • Guest VMs and OS are less privileged compared to the hypervisor. They have limited control over the hardware

    Privilege rings (no virtualization)

    • Illustrative Diagram of the different privilege levels for OS processes
    • The OS kernel, device drivers, and application processes all run at different privilege levels.

    De-privileging the guest OS

    • The VMM manages privileged instructions
    • Guest OS use the VMM to execute privileged instructions instead of directly accessing the hardware
    • This ensures isolation and prevents disruption between VMs

    Cloud Computing (Part II)

    • The presentation was from Rodrigo Bruno
    • Covered the subject of Cloud computing, part II

    Recap (hypervisor!)

    • Re-emphasizes Type 1 hypervisors, with examples like Xen, VMware ESX/ESXi and Hyper-V

    Recap (privilege rings!)

    • Explains how privileged instructions are handled in the context of virtualization
    • Shows that the guest OS (users) operates at a lower privilege ring than the hypervisor's privilege ring

    Recap (x86 virtualization problem!)

    • Details the popf instruction as a sensitive instruction in x86 architectures that can cause problems
    • Explains that the CPU will ignore popf instruction at a lower privilege ring

    Recap (virtualizing virtual memory)!

    • Diagram illustrating how virtual memory is handled within VMs via the hypervisor.

    Brainstorming

    • Focused on the topic of cloud computing and related concepts, like what cloud computing is, deployment models, service models, and Amazon Web Services

    Pre-cloud enterprise infrastructures

    • Describes the traditional IT approach to building computing infrastructure within a company (data centers)

    Cloud Computing

    • Explains the renting/subscription model of cloud computing as an alternative to building/owning a data center

    Traditional IT vs. Cloud Computing Costs

    • Shows a visual comparison reflecting fixed and variable costs over time, with cloud computing often having lower fixed costs but higher variable costs

    Nowadays, virtually every digital-based service

    • The presentation indicates that modern digital services are hosted on cloud platforms like Dropbox and Netflix. They are accessed via the internet with web interfaces or app-based interfaces.

    Main Features of Cloud Computing

    • Features of Cloud Computing: on-demand self-service, broad network access, shared resources pool, elastic scaling, measured services, and flexible pricing

    Advantages of Cloud Computing

    • Advantages of cloud computing: trade capital expenses for operational expenses, Pay-per-use, benefit from economy of scale, faster agility, and concentrate on business needs

    Cloud Computing (a definition)

    • Highlights the widely used NIST definition of cloud computing, emphasizing the key characteristics of cloud environments
    • Defines deployment models & service models, including public/private/hybrid types & services

    Deployment models

    • Describes the different types of cloud deployments, such as public, private, and hybrid clouds.
    • Public cloud exposes services to the general public, private cloud has internal usage only, and hybrid models use a mix of resources.

    Public Cloud

    • Explores the business model of public cloud providers
    • Resources are shared, which leads to decreased upfront costs

    Private Cloud

    • Explores the business model of private cloud providers
    • The cloud resources are solely available for the user or organization/company, and this often means that the user or organization is responsible for maintenance of the infrastructure

    Hybrid Cloud

    • Explores the business model of hybrid cloud providers
    • Hybrid cloud provides a mix of public & private cloud environments based on business need or operational requirement

    Service Models

    • Describes the different categories of cloud services, like IaaS, PaaS, FaaS and SaaS, encompassing infrastructure as a service, platform as a service, function as a service, and software as a service, etc

    CaaS (Car as a Service)

    • Explores business models related to owning & leasing versus subscription based services, and relates this to cloud computing concepts to illustrate a business model example.

    Cloud service models diagram

    • Shows the various components involved in on-premise, IaaS, PaaS, and SaaS cloud service models
    • Diagram shows relationships between elements, such as functions, applications, runtime, operating systems, networking, storage

    Infrastructure as a Service (IaaS)

    • Describes the infrastructure as a service (Iaas) model in the cloud.
    • Diagram illustrating a high-level summary of the different layers involved in an IaaS based solution

    Platfrom as a service (PaaS)

    • Diagram shows the different layers of an IaaS-type solution in the cloud
    • Diagram shows relationships between the different elements of the solution

    Software as a Service (SaaS)

    • Diagram of the services used in a SaaS-type solution in the cloud
    • Diagram shows relationships between the different elements of the solution

    Data Centers

    • Describes various data center deployments

    Inside a Data Center

    • Illustrates data center architecture and physical components, including server rack configurations

    Levels of Security in Data Centers

    • Depicts security measures and access control layers in a data center

    Sines 4.0

    • Focus on energy efficiency and sustainability initiatives in the Sines region

    PUE (Power Usage Effectiveness)

    • Provides a quantitative measure of energy efficiency in data centers
    • Explains a formula to calculate PUE, and how this can be used for efficiency comparisons

    Evolution of Data Centers

    • Explains how data center design has evolved over the years and different generations of designs
    • Explains how energy efficiency in data centers has improved over the years

    Aspects to Consider

    • Outlines crucial aspects to consider concerning data centers, including 24/7 access, physical security, low electricity cost, network access, and energy and heat dissipation issues

    The Importance of Electricity

    • Highlights the significance of electricity costs in data centers; that the data center portion of total operational cost (10-yr TCO per rack) for a facility comprises approximately 20% of the overall cost.

    Data Center Efficiency

    • Diagrams show power distribution, computing loads, and overall data center energy efficiency, as measured by Useful Output / Total Power In

    IT Power Load Share

    • Summarizes different power components in a data center

    Annual Electrical Cost of a 1MW Data Center

    • Illustrates the annual electrical cost, broken down based on NCPI (Network Critical Physical Infrastructure) and IT Load Electricity consumed

    Improving Data Center Efficiency

    • Discusses improving efficiency through methods, such as rightsizing NCPI equipment, and using new technologies

    Improvements

    • Outlines different approaches to improve data center efficiency, such as using less power

    Efficiency of a Typical Data Center

    • Presents performance graphs of two different data centers

    Energy vs. Performance

    • Illustrative graph of possible tradeoffs between energy consumption in a data center and the latency/performance of the data center

    Energy Carbon Intensity

    • Highlights the environmental impact and offers possible ways for companies to reduce power consumption & associated carbon emissions

    Cloud Computing Providers

    • List of notable cloud provider companies like AWS, Microsoft Azure, Google Cloud, IBM Cloud, Alibaba Cloud, and DigitalOcean

    Cloud Computing Market

    • Provides market share data for various cloud providers

    Information Security

    • Summaries of different security methods (algorithms and models)

    Security Model Based On Complete Mediation

    • Diagram detailing different modules involved in security verification in a computing system

    Trusted Computing Base (TCB)

    • Details various guidelines for a trusted computing base (TCB) in a computer system

    Real-world problem: how to exchange messages securely

    • Explains the scenario for a secure information exchange process taking into account different aspects of security like authentication, integrity and confidentiality

    Cryptography

    • Explains cryptography as a means to securing communications over insecure networks.
    • Also mentions the implementation through various algorithms for securing network communication

    Cryptographic Hash

    • Explains what a cryptographic hash is and what it can be used for

    Cryptographic Hash (SHA1 / SHA2)

    • High level details of SHA1 & SHA2 algorithms (primitives/algorithms) and their structure

    Key-based Authentication (authentication + integrity) Model

    • Highlights a model for securing authentication and integrity of messages exchanged (example: two parties wanting to ensure that a message originates from and has not been altered by some other party).

    Confidentiality

    • Details a model for encrypting messages and how this preserves confidentiality

    Cryptographic Ciphers - Shared-Secret Encryption / Symmetric Encryption

    • Overview of the components and structure of Symmetric encryption

    Cryptographic Ciphers

    • Explains the structure of Advanced Encryption Standard (AES, a symmetric cryptographic cipher), providing a high-level overview of the process, e.g., byte substitution, shift rows, mix columns.

    Cryptographic Ciphers (Rivest-Shamir-Adleman)

    • Provides information on the use of public key encryption for communications over insecure channels
    • Illustrative diagram providing example of possible operations to encrypt & decrypt, using RSA public key encryption

    Authentication + Integrity + Confidentiality

    • Explains the process involved to enforce all 3 security aspects (confidentiality, integrity, and authenticity

    Authentication + Integrity + Confidentiality (with hashing)

    • Illustrates secure information exchange processes by including hashing to ensure integrity.

    Authentication + Integrity + Confidentiality (with hashing + recv can verify)

    • Illustrative diagram illustrating the concept of authentication, integrity, and confidentiality in a secure information transmission process

    Fault Tolerance

    • Overview of faults, errors, failures, and reliable systems and how they relate to availability & reliability

    Fault Tolerance Model

    • A model of classifying and handling errors within a system

    Key Steps to Building Reliable Systems

    • Provides crucial steps to building systems that are reliable and fault-tolerant for errors in general

    Bathub Curve

    • Describes the failure rate curves over time

    Tolerating faults with Incremental Redundancy

    • Explains how redundancy can be used to correct for the occurrence of single bit flips in network communication data (e.g., 100101 changed to 000101)

    Tolerating faults with Massive Redundancy

    • Explains the concept of using full replica sets of components (modules) in a system to handle module failures

    N-modular redundancy

    • Explains N-modular Redundancy (TMR), a method for building fault-tolerence into systems using redundancy of components / modules

    Availability and Reliability

    • Explanations of Availability, Downtime, Time to Failure, and the important concept of memoryless systems in the context of fault tolerance, along with mathematical definitions of the different aspects

    Reliability of a TMR

    • Explanations of reliability concepts and mathematical relationship to time to failures

    Reliability of a TMR (long mission time)

    • Illustrative graph of a reliability analysis for a TMR (Triple Modular Redundancy) system over a long period of time (e.g., 6000 hours)

    Consistency

    • Summarizing fault tolerance issues for a system
    • Explanations of availability, fault tolerance model, incremental redundancy, and massive redundancy

    State machine replication (Massive replication)

    • Describes state machine replication methods to ensure consistent state among replicated systems

    Active Replication

    • Model for replicating states in a system

    Passive replication

    • Model for replicating states in a system

    Consensus (Paxos)

    • Explanations of Paxos protocol and how it solves consensus issues in distributed systems

    Paxos

    • Details the Paxos protocol used for achieving agreement within a system comprising a number of processes under possible failure modes / error conditions

    CAP theorem

    • Provides an overview of the CAP theorem, which highlights the trade-offs between consistency, availability, and partition tolerance in distributed systems.

    Strong consistency

    • Explains what strong consistency means in distributed systems in the context of how client read and write operations affect consistency.

    Relaxing strong consistency - Causal Consistency

    • Explains ways to enforce relaxed forms of consistency, such as Causal Consistency versus Strict Consistency

    Causal Consistency

    • Explanations of types of operations and how relationships between causal operations affect the results within a system

    Eventual Consistency

    • Explains the concept of eventually consistent systems, where updates eventually make themselves uniformly visible everywhere.

    Studying That Suits You

    Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

    Quiz Team

    Related Documents

    Cloud Computing (part I) PDF

    Description

    This quiz tests your understanding of virtualization, specifically focusing on hypervisors and their roles in managing virtual machines. Participants will explore questions about resource allocation, the benefits of virtual machines, and key concepts related to virtual machine monitors (VMM). Enhance your knowledge of how modern computing environments operate.

    More Like This

    Use Quizgecko on...
    Browser
    Open
    Browser
    Browser