Virtualization and Cloud Computing Flashcards
Virtual Machines: Host
The physical hardware that ultimately hosts all the hardware. Not to be confused with the usual network definition of “host.”
Virtual Machine (VM)
A virtual computer installed onto the host.
Virtual Machines: Hypervisor
A software abstraction layer that runs VMs as applications, effectively an operating system for operating systems.
Hypervisors: Bare-metal/Native
Bare-metal or native hypervisors are named because they install directly onto the hardware of the host machine, serving as its underlying operating system. Examples include Oracle VM Server, VMWare ESXi, and Microsoft Hyper-V.
Hypervisors: Hosted
Hosted hypervisors are software applications that run within the host machine’s primary operating system, just like any other program. Examples include Oracle VM VirtualBox, VMWare Workstation, and Windows Virtual PC.
Name the benefits of Virtualization?
- VMs using different operating systems can share a
host without conflicts. - Maintenance on one VM, like system updates,
doesn’t need to affect other VMs on the same host. - VMs are easier to back up, restore, or move to
different hardware than traditional operating system
installations. - It’s relatively easy to change or upgrade hardware on
hosts without affecting VMs, or to change the
memory or storage allocated to different VMs without
hardware changes. - Virtual machines can serve as a security sandbox,
which limits the potential damage of untrusted code.
While no sandbox is perfect, a properly designed VM
helps prevent malware or poorly designed software
from affecting the host computer or other VMs.
Virtualization requirements: Hypervisor
Hypervisors can vary widely in hardware emulated, management features, performance, ease of configuration, and licensing requirements.
Virtualization requirements: CPU
You can use any CPU in a host machine, but your performance, and choice of hypervisors, can suffer for it.
Virtualization requirements: Memory
At the least, you’ll need enough RAM to meet the needs of all the VMs you’ll be running simultaneously, in addition to whatever the hypervisor and/or host OS needs.
Virtualization requirements: Storage
VMs can be allocated actual drive partitions, but usually a VM will run a virtual disk image which exists as a file on a host partition.
Virtualization requirements: Network
Centrally hosted VDI can require fast and low-latency networks, since users will be logging into them using remote desktop software.
Virtualization requirements: Security
Virtualization can help security, but some users let that give them false confidence. VMs need to be protected from malware and other attacks just like physical systems, especially when they have network access.
What allows you to simulate private circuits over the Internet?
VPN
A hypervisor allows one host computer to support multiple guest VMs by virtually sharing its resources, like memory and processing. True or False?
True
hypervisor: It is the core that makes the process of virtualization work. True or False?
True
hypervisor: It ensures that the hosted VMs can share the host’s hardware and all its resources without interference. True or False?
True
hypervisor: It does not differ depending on the kind of hardware it emulates, especially when it comes to the CPU. True or False?
False
hypervisor: It mostly emulates the same general architecture as the host machine. True or False?
True
Five elements of cloud computing: On-demand self-service
Customers must be able to access computing resources unilaterally and automatically, without human interaction with the service provider.