WHITE PAPER VMware Infrastructure Architecture Overview VMWARE WHITE PAPER Table of Contents Physical Topology of the VMware Infrastructure Data Center .............................. .4 Virtual Data Center Architecture . .5 Hosts, Clusters and Resource Pools ..................................................... .6 VMware VMotion, VMware DRS and VMware HA .......................................... .7 Networking Architecture. .8 Storage Architecture .................................................................. .9 VMware Consolidated Backup ......................................................... 10 ESX Server External Interfacing Components ........................................... 10 VirtualCenter Management Server Architecture ......................................... 11 Conclusion .......................................................................... 13 VMWARE WHITE PAPER VMware Infrastructure Architecture Overview VMware® Infrastructure is the industry’s first full infrastruc- ture virtualization suite that allows enterprises and small busi- What is Virtualization and What are Virtual nesses alike to transform, manage and optimize their IT systems Machines? infrastructure through virtualization. VMware Infrastructure delivers comprehensive virtualization, management, resource Virtualization is an abstraction layer that decouples optimization, application availability and operational automa- the physical hardware from the operating system to tion capabilities in an integrated offering. deliver greater IT resource utilization and flexibility. Virtualization allows multiple virtual machines, with Figure 1-1: VMware InfrastructureVMware Infrastructure heterogeneous operating systems (e.g., Windows 00 Server and Linux) and applications to run in iso- Consolidated lation, side-by-side on the same physical machine. DRS HA Backup A virtual machine is the representation of a physical VirtualCenter Management Server machine by software. It has its own set of virtual hardware (e.g., RAM, CPU, NIC, hard disks, etc.) upon Virtual Machines which an operating system and applications are App App App App App App App App App App loaded. The operating system sees a consistent, OS OS OS OS OS OS OS OS OS OS normalized set of hardware regardless of the actual physical hardware components. VMware virtual Virtual SMP ESX Servers VMFS machines contain advanced hardware features such as 64-bit computing and virtual symmetric multipro- cessing. For more information on virtualization, please read the Virtualization Overview VMware white paper. Enterprise Servers Enterprise Storage • Virtual Infrastructure Web Access – A Web interface for virtual Enterprise Network machine management and remote consoles access • VMware VMotion™ – Enables the live migration of running VMware Infrastructure includes the following components as virtual machines from one physical server to another with shown in Figure 1-1: zero downtime, continuous service availability and complete • VMware ESX Server – A production-proven virtualization transaction integrity layer run on physical servers that abstract processor, memory, • VMware High Availability (HA) – Provides easy-to-use, cost- storage and networking resources to be provisioned to effective high availability for applications running in virtual multiple virtual machines machines. In the event of server failure, affected virtual • VMware Virtual Machine File System (VMFS) – A high-perfor- machines are automatically restarted on other production mance cluster file system for virtual machines servers that have spare capacity • VMware Virtual Symmetric Multi-Processing (SMP) – Enables • VMware Distributed Resource Scheduler (DRS) – Intelligently a single virtual machine to use multiple physical processors allocates and balances computing capacity dynamically simultaneously across collections of hardware resources for virtual machines • VirtualCenter Management Server – The central point for • VMware Consolidated Backup – Provides an easy to use, configuring, provisioning and managing virtualized IT infra- centralized facility for agent-free backup of virtual machines. It structure simplifies backup administration and reduces the load on ESX • Virtual Infrastructure Client (VI Client) – An interface that Server installations allows administrators and users to connect remotely to the • VMware Infrastructure SDK – Provides a standard interface VirtualCenter Management Server or individual ESX Server for VMware and third-party solutions to access VMware installations from any Windows PC Infrastructure VMWARE WHITE PAPER The following sections describe the architecture of VMware Storage Networks and Arrays Infrastructure, beginning with the elements that make up Fiber Channel SAN arrays, iSCSI SAN arrays and NAS arrays its physical topology, followed by the virtual, or logical, view are widely-used storage technologies supported by VMware of VMware Infrastructure where the relationships between Infrastructure to meet different data center storage needs. the virtual architectural elements and the physical world Sharing the storage arrays between (by connecting them to) are explored. Lastly, the architectures of two core VMware groups of servers via storage area networks allows aggregation Infrastructure components are discussed in further detail. of the storage resources and provides more flexibility in provi- sioning them to virtual machines. Physical Topology of the VMware Infrastructure Data Center IP Networks Each computing server can have multiple gigabit Ethernet With VMware Infrastructure, IT departments can build a network interface cards (NICs) to provide high bandwidth and virtual data center using their existing industry standard reliable networking to the entire data center. technology and hardware. There is no need to purchase specialized hardware. In addition, VMware Infrastructure allows Management Server users to create a virtual data center that is centrally managed The VirtualCenter Management Server provides a convenient by management servers and can be controlled through a wide single point of control to the data center. It runs on Windows selection of interfaces. 00 Server to provide many essential data center services such Figure 1-2: VMware Infrastructure Data Center Physical Building Blocks as access control, performance monitoring and configuration. It unifies the resources from the individual computing servers to VI Web be shared among virtual machines in the entire data center. As Terminal VirtualCenter Client Browser Management Server shown in Figure 1-, VirtualCenter Management Server accom- plishes this by managing the assignment of virtual machines to the computing servers. VirtualCenter Management Server also manages the assignment of resources to the virtual machines Server Server Server Group 1 Group 2 Group 3 within a given computing server based on the policies set by the system administrator. Figure 1-3: VirtualCenter Management Server centrally manages the assign- ment of virtual machines to physical servers VirtualCenter Management Server cluster1 Virtual Machines App App App App App OS OS OS OS OS RP2 host1 Fiber Channel Switch Fabric / IP Network ESX Server Manage VM VM RP1 RP3 VM VM Virtual Machines Virtual Machines Virtual Machines Fiber Channel iSCSI NAS App App App App App App App App App App App App App App App Storage Storage Storage VM VM Array Array Array OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS datastores ESX Server ESX Server ESX Server VM As Figure 1- shows, a typical VMware Infrastructure data center network A consists of basic physical building blocks such as x86 comput- network B ing servers, storage networks and arrays, IP networks, a manage- ment server and desktop clients. Computing Servers Physical Servers The computing servers are industry standard x86 servers that run VMware ESX Server on the “bare metal.” Each computing server is referred to as a standalone Host in the virtual environ- ment. A number of similarly configured x86 servers can be grouped together with connections to the same network and storage subsystems to provide an aggregate set of resources in the virtual environment, called a Cluster. 4 VMWARE WHITE PAPER Computing servers will continue to function even in the • Virtual machines unlikely event that VirtualCenter Management Server became A Host is the virtual representation of the computing and unreachable (e.g., the network is severed). Computing servers memory resources of a physical machine running ESX Server. can be managed separately and will continue to run their When one or more physical machines are grouped together assigned virtual machines based on the resource assignments to work and be managed as a whole, the aggregate comput- that were last set. Once the VirtualCenter Management Server ing and memory resources form a Cluster. Machines can be becomes available, it can manage the data center as a whole dynamically added or removed from a Cluster. Computing and again. memory resources from Hosts and Clusters can be finely parti- The architecture of VirtualCenter Management Server will be tioned into a hierarchy of Resource Pools. described in detail in later sections. Datastores are virtual representations of combinations of Desktop Clients underlying physical storage resources in the data center. These physical storage resources can come from the local SCSI disks of VMware Infrastructure provides a selection of interfaces for the server, the Fiber Channel SAN disk arrays, the iSCSI SAN disk data center management