Podcast Beta
Questions and Answers
What is a key feature of virtualization?
Which type of virtualization involves a software layer mediating between virtual machines and the hardware?
What is paravirtualization primarily characterized by?
What differentiates containerization from server virtualization?
Signup and view all the answers
Which of the following statements about full virtualization is true?
Signup and view all the answers
What enhancement does hardware-assisted virtualization provide?
Signup and view all the answers
Which technology is an example of a hypervisor used in full virtualization?
Signup and view all the answers
What is a disadvantage of full virtualization compared to paravirtualization?
Signup and view all the answers
What characterizes a bare-metal hypervisor?
Signup and view all the answers
What is the primary advantage of live migration of virtual machines?
Signup and view all the answers
How are virtual machine images utilized in hypervisors?
Signup and view all the answers
What does containerization rely on for its operation?
Signup and view all the answers
What is the main purpose of the Packer tool?
Signup and view all the answers
What is Vagrant primarily used for?
Signup and view all the answers
Which of the following best describes OS-level virtualization?
Signup and view all the answers
What type of files does Packer use for configurations?
Signup and view all the answers
Study Notes
Virtualization
- Virtualization allows multiple operating systems (guest operating systems) to run on the same physical hardware.
- From a user’s perspective, a virtual server behaves like a physical server.
- Virtualization enables on-demand, internet-connected virtual servers which form the basis of cloud computing.
- Containerization is a new form of OS abstraction.
Virtualization vs. Containerization
- Server virtualization involves guest operating systems running on virtualized hardware.
- Containerization is OS-level virtualization, where containers are isolated processes that share the host operating system's kernel and services.
Hypervisor
- Hypervisor, or virtual machine monitor, is a software layer that manages virtual machines (VMs) and the underlying hardware.
- Examples include VMware ESX, XenServer, FreeBSD bhyve, and the Linux kernel-based virtual machine (KVM).
Hypervisor (cont.)
-
Full virtualization emulates hardware components, allowing guest systems to run without modifications.
- Performance penalty due to hypervisor translation between actual and virtual hardware.
- Separate tasks of managing multiple environments (virtualization) and emulating hardware (emulation).
- QEMU is a common emulation package.
-
Paravirtualization involves modified guest operating systems that work with the hypervisor for hardware access, leading to performance improvements.
- Guest operating systems require modifications for this mode.
- Xen hypervisor is an example.
Hypervisor (cont.)
-
Hardware-assisted virtualization leverages CPU features like Intel VT and AMD-V to accelerate virtualization.
- CPU and memory controller are virtualized in hardware, resulting in improved performance.
- Guest operating systems needn't be aware of running on a virtualized CPU.
Type 1 vs. Type 2 Hypervisors
-
Type 1 hypervisors (bare-metal or native) run directly on the hardware without an underlying operating system.
- Examples include XenServer and VMware ESXi.
-
Type 2 hypervisors are user-space applications that run on top of another operating system.
- Examples include VMware Workstation and VirtualBox.
Live Migration
- Virtual machines can be moved between hypervisors on different hardware without service interruptions or connectivity loss.
- Memory dance involves copying changes from source to destination hypervisor for seamless migration.
- Live migration helps for high-availability, load balancing, disaster recovery, server maintenance, and system flexibility.
Virtual Machine Images
- They are templates containing configured operating systems that hypervisors can load and execute.
- Snapshots of virtual machines can be taken to create images.
- Images are portable across systems despite hardware differences.
- Conversion tools help in transferring images between hypervisors.
Containerization
- Containerization involves OS-level virtualization without a hypervisor, relying on kernel features for process isolation.
- Each container has a private root filesystem and process namespace.
- Containers share the host OS's kernel and services but have restricted access to files and resources.
- Low resource overhead and near-native performance compared to server virtualization.
- Limitation: cannot run multiple operating systems.
- Examples include Linux's LXC, Docker containers, and FreeBSD jails.
- Containers are often used on VMs for cloud-based deployments.
Packer
- Tool for building virtual machine images using specifications.
- Supports various virtualization and cloud platforms.
- Packer uses JSON files to define image configurations.
- Instead of manually applying changes, you modify a template to define the image.
Vagrant
- A wrapper layer for virtualization platforms like VMware, VirtualBox, and Docker.
- Simplifies provisioning and configuration of virtual development environments.
- Focuses on creating disposable, preconfigured development environments that closely resemble production environments.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers key concepts of virtualization and containerization, including the differences between server virtualization and OS-level virtualization. It also delves into the role of hypervisors in managing virtual machines and their significance in cloud computing.
