Virtualization and Cloud Computing Flashcards
Virtualization
- is a process that creates a software environment to emulate a
computer’s hardware and BIOS - Allows multiple OSs to run on the same physical computer at the same time
A virtual machine (VM)
is the virtual environment that emulates a physical computer’s hardware and BIOS
A guest OS
is the operating system installed on a VM
A host computer
is the physical computer on which the VM software is installed
Virtualization software?
creates and manages VMs and creates the virtual environment in which a guest OS is installed
The hypervisor
creates and monitors the virtual hardware environment, which allows multiple VMs to share physical hardware resources
A type 1 hypervisor
runs directly on the host computer’s hardware and controls and monitors guest OSs (also called bare-metal virtualization)
A type 2 hypervisor
is installed in a general-purpose host OS, and the host OS accesses host hardware on behalf of the guest OS (also called hosted virtualization)
A virtual disk
consists of files residing on the host computer that represent a virtual machine’s hard
drive
A virtual network
is a network configuration created by virtualization
A snapshot
is a partial copy of a VM made at a particular moment
Hosted Virtualization
- uses a type 2 hypervisor
- It has an advantage of supporting a wider variety of guest OSs because there are few incompatibility problems between the guest OS and hardware
− You install the virtualization software on your computer and begin creating virtual machines
- Hardware requirements include enough memory to support the host and guest
OSs, adequate CPU power, and enough space to store the virtual disk
VMware Workstation Pro
− Allows you to configure the NIC on your VM to use one of the five virtual network options or create your own custom virtual network
- Five preconfigured options:
− Bridged, NAT, host-only, custom, LAN segment
Which of the following implements OS virtualization by being installed in a
general-purpose host OS and the host OS accesses host hardware on behalf of
the guest OS?
− A) hosted virtualization
− B) virtual disk
− C) type 1 hypervisor
− D) bare-metal hypervisor
hosted virtualization
Bare-Metal Virtualization
- use a type 1 hypervisor and are targeted
mainly for production virtualization in datacenters - They are installed directly on hardware and have more stringent host machine
requirements - They offer more features for managing VMs than hosted virtualization
Live migration
− VMs can be migrated to new hardware while they’re running for performance
and reliability improvements with practically no downtime
- Dynamic provisioning
− Advanced VM management systems can deploy VMs and storage dynamically to meet application requirements
Microsoft Hyper-V
hypervisor service that allows Windows Server to host multiple virtual machines
Application Virtualization
- Whole-system virtualization allows you to run an OS in a VM that is totally different from the OS running on the host
− This type of virtualization is often used to isolate a single application from the
host for testing purposes or when multiple instances of the same application
must run on one host
- To mitigate resource overhead required for whole-system virtualization, many
cloud providers are turning to application virtualization in the form of containers
A container
is a virtualized software environment in which an application can run but is isolated from the rest of the OS and other applications
- Windows Sandbox
is a feature available with Windows Pro and Enterprise that provides a temporary isolated environment in which to run an application
− It is built on containers technology
− It is a desktop OS feature primarily designed to allow you to test an application to make sure it will not interfere with any existing applications
-it looks like a full VM, but it is actually sharing much of the host OS that is loaded into RAM
Cloud computing
is a networking model in which data, applications, and processing power are managed by servers on the Internet
− Users of resources pay for what they use rather than for the equipment and
software needed to provide the resources
- Benefits:
− Reduced physical plant costs
− Reduced upfront costs
− Reduced personnel costs
There are three main categories of cloud computing:
- Software as a service
− Platform as a service
− Infrastructure as a service
- The phrase as a service means?
the resource resides on another server or
network from the one using the resource
Software as a Service
- SaaS is also called hosted applications or on-demand applications
− The best-known examples are Google Apps and Microsoft Office 365
- It is usually offered as a subscription based on the number of users
- Customers can take advantage of new software editions much faster
- SaaS is available anywhere the customer has a connection to the Internet
Platform as a Service
- PaaS is also called hosted platform and is similar to SaaS, but the customer
develops applications with the service provider’s tools and infrastructure
− The customer develops and owns the application and then delivers it to a
third party
- The most common PaaS products are:
− Salesforce.com’s Apex, Azure for Windows, Google’s AppEngine for Python
and Java, WaveMaker for Ajax, and Engine Yard for Ruby on Rails
Infrastructure as a Service
- IaaS is also called hosted infrastructure; it allows a company to use storage or
entire virtual servers - If a customer needs another 100 GB of storage space, they can pay for the
space without worrying about how that space is actually provided - If a customer needs another server, they pay for the amount of processing and
storage the additional server actually requires
− Customers rent the resources they are using but are responsible for
application installations and upgrades
- Public cloud services
− Cloud services are delivered by a third-party provider
- Private cloud services
− When a company delivers cloud services to its own employees through the use of virtualization technologies
− Deployed from the company’s own datacenter
− Examples of virtualization technologies:
VMware and Microsoft Hyper-V
Which of the following is a virtualized software environment in which an
application can run but is isolated from the rest of the OS and other
applications?
− A) software as a service (SaaS)
− B) cloud computing
− C) container
− D) Hyper-V
− C) container
