VMware Vsphere Virtualization

• Overall architecture

Main components:

1) ESXi

The underlying virtualization layer, which is used to virtual the physical server into a resource pool, provides the management interface and facilitates the management of other management components, whose entity form is the ISO file, which can be directly installed on the server bare metal on the boot cd;

Installed on the physical server, is actually a Linux kernel operating system, only after you install ESXi, you can create a virtual machine on it. Can be understood as VMware Workstation on your desktop, except that ESXi does not run on the operating system (because it is the operating system) and calls hardware resources directly for the virtual machine

2) vsphere Client

Is the client software installed on the Windows system, enter the IP of the corresponding ESXi host after logging in to manage it, or enter the IP of the vcenter server to manage the entire data center.

3) VCenter

Server-side software that centrally manages ESXi hosts, installed in Windows Server 2008R2 or above, and maintains information about the functional components in the data center through SQL 2008R2 or later versions of the database (other databases also have version requirements). There are also versions installed in the Linux environment

4) vsphere Web Client

Through the browser input vcenter server's IP, you can enter the entire virtualized data center management interface, after vsphere5.0, VMware is gradually weakening the role of vsphere client, Many advanced features (such as enhanced vmotion) can now be implemented in the Web client

• Several major virtualization

ESXi是VMware公司研发的虚拟机服务器，ESXi已经实现了与Virtual Appliance Marketplace的直接整合，使用户能够即刻下载并运行虚拟设备。这为即插即用型软件的交付与安装提供了一种全新和极其简化的方式。通过iso镜像（比如VMWare ESXi 5.5.iso）在服务器上安装ESXi虚拟化服务，接着在本地PC机（win10）上安装VMware vSphere Clent客户端工具去连接远程的ESXi服务器，然后在VMware vSphere Clent工具界面里进行虚拟机的创建和管理。

------------------------------------------------------------------------------------------------------------------------- XenServer是思杰公司基于Xen的虚拟化服务器，Citrix XenServer是一种全面而易于管理的服务器虚拟化平台，基于强大的Xen Hypervisor程序之上。 通过iso镜像（比如XenServer-7.1.1- install - cd .iso）在服务器上安装XenServer服务，接着在本地PC机（win10）上安装Citrix XenCenter客户端 工具去连接远程的XenServer服务器，然后在Citrix XenCenter工具界面里进行虚拟机的创建和管理。 ------------------------------------------------------------------------------------------------------------------------- KVM（Kernel-based Virtual Machine）是一个开源的系统虚拟化模块，自Linux 2.6.20之后集成在Linux的各个主要发行版本中。它使用Linux自身 的调度器进行管理，所以相对于Xen，其核心源码很少。KVM目前已成为学术界的主流VMM之一。KVM的虚拟化需要硬件支持（如Intel VT技术或者AMD V技术)， 是基于硬件的完全虚拟化。而Xen早期则是基于软件模拟的Para-Virtualization，新版本则是基于硬件支持的完全虚拟化。但Xen本身有自己的进程调度器， 存储管理模块等，所以代码较为庞大。广为流传的商业系统虚拟化软件VMware ESX系列是基于软件模拟的Full-Virtualization。 KVM虚拟化部署有以下几种方法： 方法一：通过自身的virt-manager工具进行虚拟机的创建和管理 方法二：通过WebVirtMgr工具进行虚拟机的创建和管理 方法三：通过OpenStack工具进行虚拟机的创建和管理。

VMware Vsphere Virtualization