System Fundamentals 1 - Virtualization Basics

System Fundamentals 1 - BINCT 1

• Module 3 covers Virtualization and Cloud Computing Fundamentals.
• Learning objectives include describing virtualization components, using and describing hosted and bare-metal virtualization, application virtualization, and cloud computing.
• Virtualization is a process that creates a software environment to emulate a computer's hardware and BIOS. This allows multiple operating systems to run on the same physical machine at the same time.
• A virtual machine (VM) is a virtual environment emulating physical hardware and BIOS.
• A guest OS is an operating system on a VM.
• A host computer is the physical machine where the VM software runs.
• Virtualization software creates and manages VMs and the virtual environment where the guest OS is installed.
• Hypervisors create and monitor the virtual hardware environment allowing VMs to share resources.
• Type 1 hypervisors run directly on the host's hardware and control guest OSs (bare-metal).
• Type 2 hypervisors run within a general-purpose host OS, allowing the host OS to access the hardware on behalf of the guest OS (hosted virtualization).
• A virtual disk is comprised of files residing on the host computer that act as a hard drive for the virtual machine.
• A virtual network is a network configuration created by virtualization software.
• A snapshot is a partial copy of a VM at a specific moment.

Hosted Virtualization

• Hosted virtualization uses a type 2 hypervisor.
• It's easier to use, supports a wider range of guest OSs with fewer compatibility problems between the guest OS and hardware.
• Users install virtualization software and start creating virtual machines.
• Hardware requirements include enough memory to support both host and guest OSs, adequate CPU power and enough space to store the virtual disk.
• Applications for hosted virtualization include OS or software training, application isolation, network isolation, software development, what-if scenarios, legacy application use, and physical-to-virtual conversion.
• Common hosted virtualization products include VMware Workstation Pro, VMware Workstation Player, VMware Fusion, Parallels Desktop for Mac, and VirtualBox.

Using VMware Workstation Pro

• A free trial version is available for 30 days.
• A wizard guides the user through creating a virtual machine.
• Flexible networking options are available, including configuring the network interface card (NIC) to use one of five virtual network, or creating a custom virtual network. Pre-configured options for networking include: bridged, NAT, host-only, custom, and LAN segment.
• VMware Tools can improve performance and improve integration between the guest and host devices.

Using VMware Workstation Player

• A stripped-down version of VMware Workstation Pro.
• The wizard for creating VMs is very similar to the one in Pro, also providing the ability to download a virtual appliance with a pre-configured guest OS and applications or network services.
• Useful for new users and training environments.

Using VirtualBox

• VirtualBox runs on various host operating systems: Windows, macOS, Linux, and Solaris.
• Supports a wide range of guest operating systems.
• VM creation is done through a wizard that guides the user through the process.
• VirtualBox user interface features a console for creating VMs and viewing their status.

Knowledge Check 1

• Hosted virtualization is implemented when the hypervisor is installed in a general-purpose host OS, and the host OS accesses the hardware on behalf of the guest OS.

Bare-Metal Virtualization

• Uses type 1 hypervisors, mainly for production in datacenters.
• Installed directly on hardware, therefore requiring more stringent host machine requirements.
• Better features for managing VMs than hosted virtualization but is more complicated to set-up and use.
• Applications include consolidating servers, retiring hardware, making optimal use of multicore high-performance servers, maintaining application separation, maximizing rack or floor space, reducing cooling and power requirements, testing installations, and upgrades, and testing preconfigured applications.
• Also supports live migration of VMs to new hardware, leading to performance and reliability improvements with little to no downtime and dynamic provisioning, allowing for VM and storage deployment to adapt application needs.

Bare-Metal Virtualization Products

• Microsoft Hyper-V
• Citrix XenServer
• VMware vSphere (uses VMware ESXi hypervisor)

Using Hyper-V

• Microsoft's type 1 hypervisor that runs on Windows Server and Windows 10.
• Installed from Server Manager by using the "Turn Windows features on or off" tool.
• Hyper-V Manager console is installed on another computer to create and manage VMs.
• Virtual switches need to be created to manage VMs.
• Management actions include connecting, setting, starting, checkpointing, moving, exporting, renaming, deleting, and enabling replication.

Using VMware vSphere

• Type 1 hypervisor, similar to Hyper-V.
• Runs on the VMware ESXi hypervisor, uses a simple textual menu based interface.
• Management interface can be accessed through a Web browser on a separate computer via the vSphere Web Client.
• Networking includes a virtual switch, vSwitch0 by default, which connects to a physical NIC, and requires a minimum of two ports: one for management and one for VM traffic.
• ESXi installation will create two default port groups: Management Network and VM Network.
• Creating VMs within vSphere uses a wizard from the vSphere Web Client to guide the user through the steps including assigning a name, choosing guest OS, datastore, and hardware options.

Application Virtualization

• Allows running an OS in a VM that's different from the host OS, commonly used to isolate a single application for testing purposes, or when multiple instances of the same application need to run on a single host.
• Cloud providers use application virtualization in the form of containers to mitigate resource overhead for whole-system virtualization.

Containers

• Virtualized software environment that allows applications to run, but isolated from other applications and OS.
• Containers are essentially lightweight VMs with shared OS, file system, and network configuration components.
• Docker is a container management platform for use with Linux distributions and Windows Server 2016.

Windows Sandbox

• A feature in Windows Pro and Enterprise for temporary, isolated testing environments built on container technology.
• Allows isolating applications from other applications on the host system.
• Can be set up on a physical or virtual machine.
• Installed from Windows Features.

Cloud Computing

• A networking model where data, applications, and processing power are on internet-accessible servers.
• Users pay for resources based on use.
• Benefits include reduced physical plant, upfront, and personnel costs.
• Three main cloud categories: Software as a service (SaaS), Platform as a service (PaaS), and Infrastructure as a service (IaaS).
• SaaS provides on-demand or hosted applications like Google Apps or Microsoft Office 365, subscription-based and accessible via Internet connection.
• PaaS is similar to SaaS where users develop applications, but using provider tools and infrastructure, with the developed application being delivered to a third-party.
• IaaS is a service that allows a company using the cloud to get their storage and servers, paying only for what they use.

Private Cloud vs Public Cloud

• Private cloud services are delivered to company employees using company virtualization technologies. They are deployed from the company's own data center.
• Public cloud services are provided by third-party providers.

Explore the fundamentals of virtualization and cloud computing in this quiz based on Module 3 of the System Fundamentals 1 course. Test your knowledge on components like virtual machines, hypervisors, and the differences between hosted and bare-metal virtualization.