Overview of Virtualization

• The knowledge point of virtualization

1 . Breaking the hard connection between the physical hardware and the operating system and the applications running on it

Virtualization: Multiple operating systems can be run on a single physical machine.

Hard connection: Only one operating system can be run on a physical machine

Virtualization technology virtualization of physical resources

Hardware can only be used natively before the physical machine is not virtualized

After virtualization, the hardware is used by virtual machines (running multiple operating systems), and each virtual machine is independent, and all virtual machines can share the resources of that physical computer in a variety of environments.

2. Virtualized Infrastructure

Vmware VSphere(the solution, not software, consists of several software) builds the entire virtual infrastructure, which includes thousands of interconnected physical computers and storage devices.

You can dynamically move resources and processing power and allocate hardware resources.

Local storage: Local hard disk

Networked storage: Provides storage space for sharing over a network

3. Cloud computing

Virtualization technology is the foundation of cloud computing

The resources and services that users use are provided by the cloud provider's centralized resources.

cloud computing relies on scalable elastic models to provide IT Services, the model relies on virtualization.

4. Server Integration

A: Equipment cost savings

B: Improve resource utilization, integration rate

You can limit the physical resources that you need to manage, support, store, and purchase.

For example: Software development companies in software testing, if not server integration (virtualization), the need to purchase a physical machine, if the virtualization is only a small number of physical machines, saving resources.

5. Business Continuity

Embodied in the management of cost savings, efficiency, reduce disruption time, or even eliminate.

with virtualization, you can shorten or even eliminate planned and unplanned downtime. Migrate to other hosts in real time, perform maintenance at any time, without disrupting service, without impacting service uptime. With vsphere featuressuch as high Availability(HA ) and faulttolerance(fault tolerance FT) , Reduce unplanned downtime.

Planning: Restarting or shutting down when you want to replace hardware, or if it's not a hot-swappable hardware Device

Unplanned: A physical machine suddenly restarts or shuts down and the server stops serving

The virtual machine is hardware independent.

6.vsphere

VMware is the company that introduces a set of server virtualization solutions.

The core component is VMware ESXi(original esx), a system that can be installed and run on bare metal (native architecture).

Workstation is an alien architecture, dependent on the host operating system.

Connection can be remotely controlled via client

Vsphere consists of the virtualization layer, management layer, interface layer

Virtualization Layer:

Infrastructure services: (Virtualization, aggregation, allocation of resources, infrastructure resources) compute services, storage services, network services

Computing Services: The CPU, memory scheduling and allocation.

Storage services: Efficient use and management of storage technology sets, virtual disks, and allocation of storage resources (scheduling) in virtual environments.

NETWORK Service: Host host's network card and external network communication (physical host), provide network communication.

Application services: Service set. Availability, security, scalability

Availability of: HA\FA High availability, utilization. (no matter what happens, the service is uninterrupted.) )

Security: Assistive Tools VShield Security

Scalability :a: resources (Increase the number of physical hosts at any time)

B: Change the virtual machine resources without shutting down the machine directly (dynamic)

Management:VMware vcenter Server is the central point for configuring and managing virtualized IT environments. Equivalent to management core, centralized management, unified management. Like VMs, Citrix, Microsoft all need

Interface Layer: GUI Clients (client or Web client) Access the vsphere data Center. You can also access the data center by using the command line interface and the SDK for automatic management of the client. Provides administrators with management clients to manage the entire virtual host (vcenter).

Vsphere Components and features:

The core components are: VMware ESXi and VMware vcenter Server

Esxi: A virtualized platform for creating and running virtual machines. Virtualize processors, memory, storage, and resources into multiple virtual machines.

Vcenterserver: A Windows service that acts as a central administrator for ESXi hosts connected to the network . For monitoring and managing physical and virtual infrastructures.

Vclient: Remote connection to vcenter or esxi interface

Webclient: Connect to the Vcenter interface from a Web browser .

Vmotion: Migrates power-powered virtual machines from one physical server to another, maintaining 0 downtime, continuous service availability, and transaction integrity. But not from one data center to another ( a virtualized environment ).

Vspherestorage vmotion: You can contract virtual machine files between data stores without disrupting service. (Migration between storage svmotion)

Vspherehigh availability(HA): provides high availability.

Vspherefault Tolerance (FT): Continuous availability through replica virtual machines (shadow VMs), equivalent to backing up virtual machines.

physical topology of the data center: by a basic physical building block (for example: virtualized server (physical host ESXI, host host), storage network and array,IP Network, Management Server, desktop client).

memory networks and Arrays: Fibre Channel San arrays,ISCSI san arrays, and NAS arrays.

Ip Network: The compute server can have multiple physical network adapters, providing high bandwidth and reliable network connectivity.

Vcenter unifies the resources in each compute server so that these resources are shared among virtual machines throughout the data center.

Rationale: Manages the allocation of virtual machines to compute servers, and the allocation of resources to virtual machines within a given compute server, based on policies set by the system administrator.

Overview of Virtualization