W H I T E P A P E R
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`VMware Infrastructure Architecture Overview
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`WHITE PAPER
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`VMware Infrastructure Architecture Overview
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`WIZ, Inc. EXHIBIT - 1074
`WIZ, Inc. v. Orca Security LTD.
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`VMware white paper
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`Table of Contents
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`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
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`VMware white paper
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`VMware Infrastructure architecture Overview
`VMware® Infrastructure is the industry’s first full infrastruc-
`ture virtualization suite that allows enterprises and small busi-
`nesses alike to transform, manage and optimize their IT systems
`infrastructure through virtualization. VMware Infrastructure
`delivers comprehensive virtualization, management, resource
`optimization, application availability and operational automa-
`tion capabilities in an integrated offering.
`
`Figure 1-1: VMware Infrastructure
`VMware Infrastructure
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` DRS
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`HA
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`Consolidated
`Backup
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`VirtualCenter Management Server
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`Virtual Machines
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`Virtual SMP
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`ESX Servers
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`VMFS
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`what is Virtualization and what are Virtual
`Machines?
`Virtualization is an abstraction layer that decouples
`the physical hardware from the operating system to
`deliver greater IT resource utilization and flexibility.
`Virtualization allows multiple virtual machines, with
`heterogeneous operating systems (e.g., Windows
`00 Server and Linux) and applications to run in iso-
`lation, side-by-side on the same physical machine.
`A virtual machine is the representation of a physical
`machine by software. It has its own set of virtual
`hardware (e.g., RAM, CPU, NIC, hard disks, etc.) upon
`which an operating system and applications are
`loaded. The operating system sees a consistent,
`normalized set of hardware regardless of the actual
`physical hardware components. VMware virtual
`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.
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`Enterprise Servers
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`Enterprise Network
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`Enterprise Storage
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`VMware Infrastructure includes the following components as
`shown in Figure 1-1:
`• VMware ESX Server – A production-proven virtualization
`layer run on physical servers that abstract processor, memory,
`storage and networking resources to be provisioned to
`multiple virtual machines
`• VMware Virtual Machine File System (VMFS) – A high-perfor-
`mance cluster file system for virtual machines
`• VMware Virtual Symmetric Multi-Processing (SMP) – Enables
`a single virtual machine to use multiple physical processors
`simultaneously
`• VirtualCenter Management Server – The central point for
`configuring, provisioning and managing virtualized IT infra-
`structure
`• Virtual Infrastructure Client (VI Client) – An interface that
`allows administrators and users to connect remotely to the
`VirtualCenter Management Server or individual ESX Server
`installations from any Windows PC
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`• Virtual Infrastructure Web Access – A Web interface for virtual
`machine management and remote consoles access
`• VMware VMotion™ – Enables the live migration of running
`virtual machines from one physical server to another with
`zero downtime, continuous service availability and complete
`transaction integrity
`• VMware High Availability (HA) – Provides easy-to-use, cost-
`effective high availability for applications running in virtual
`machines. In the event of server failure, affected virtual
`machines are automatically restarted on other production
`servers that have spare capacity
`• VMware Distributed Resource Scheduler (DRS) – Intelligently
`allocates and balances computing capacity dynamically
`across collections of hardware resources for virtual machines
`• VMware Consolidated Backup – Provides an easy to use,
`centralized facility for agent-free backup of virtual machines. It
`simplifies backup administration and reduces the load on ESX
`Server installations
`• VMware Infrastructure SDK – Provides a standard interface
`for VMware and third-party solutions to access VMware
`Infrastructure
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`

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`VMware white paper
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`The following sections describe the architecture of VMware
`Infrastructure, beginning with the elements that make up
`its physical topology, followed by the virtual, or logical, view
`of VMware Infrastructure where the relationships between
`the virtual architectural elements and the physical world
`are explored. Lastly, the architectures of two core VMware
`Infrastructure components are discussed in further detail.
`
`Physical Topology of the VMware
`Infrastructure Data Center
`With VMware Infrastructure, IT departments can build a
`virtual data center using their existing industry standard
`technology and hardware . There is no need to purchase
`specialized hardware. In addition, VMware Infrastructure allows
`users to create a virtual data center that is centrally managed
`by management servers and can be controlled through a wide
`selection of interfaces.
`Figure 1-2: VMware Infrastructure Data Center Physical Building Blocks
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`VirtualCenter
`Management
`Server
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`VI
`Client
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`Web
`Browser
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`Terminal
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`Server
`Group 1
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`Server
`Group 2
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`Server
`Group 3
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`Storage Networks and Arrays
`Fiber Channel SAN arrays, iSCSI SAN arrays and NAS arrays
`are widely-used storage technologies supported by VMware
`Infrastructure to meet different data center storage needs.
`Sharing the storage arrays between (by connecting them to)
`groups of servers via storage area networks allows aggregation
`of the storage resources and provides more flexibility in provi-
`sioning them to virtual machines.
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`IP Networks
`Each computing server can have multiple gigabit Ethernet
`network interface cards (NICs) to provide high bandwidth and
`reliable networking to the entire data center.
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`Management Server
`The VirtualCenter Management Server provides a convenient
`single point of control to the data center. It runs on Windows
`00 Server to provide many essential data center services such
`as access control, performance monitoring and configuration.
`It unifies the resources from the individual computing servers to
`be shared among virtual machines in the entire data center. As
`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
`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
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`Virtual Machines
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`ESX Server
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`Fiber Channel Switch Fabric / IP Network
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`VirtualCenter Management Server
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`Manage
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`Fiber Channel
`Storage
`Array
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`iSCSI
`Storage
`Array
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`NAS
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`Array
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`ESX Server
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`As Figure 1- shows, a typical VMware Infrastructure data center
`consists of basic physical building blocks such as x86 comput-
`ing servers, storage networks and arrays, IP networks, a manage-
`ment server and desktop clients.
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`Computing 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.
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`Physical Servers
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`Computing servers will continue to function even in the
`unlikely event that VirtualCenter Management Server became
`unreachable (e.g., the network is severed). Computing servers
`can be managed separately and will continue to run their
`assigned virtual machines based on the resource assignments
`that were last set. Once the VirtualCenter Management Server
`becomes available, it can manage the data center as a whole
`again.
`The architecture of VirtualCenter Management Server will be
`described in detail in later sections.
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`Desktop Clients
`VMware Infrastructure provides a selection of interfaces for
`data center management and virtual machine access. Users
`can choose the interface that best meets their needs: Virtual
`Infrastructure Client (VI Client), Web Access through a Web
`browser, or terminal services (such as Windows Terminal
`Services or Xterm).
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`Virtual Data Center architecture
`VMware Infrastructure virtualizes the entire IT infrastructure
`including servers, storage and networks. It aggregates these
`heterogeneous resources and presents a simple and uniform
`set of elements in the virtual environment. With VMware
`Infrastructure, IT resources can be managed like a shared
`utility and dynamically provisioned to different business
`units and projects without worrying about the underlying
`hardware differences and limitations .
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`cluster1
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`network A
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`network B
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`Figure 1-4: Virtual Data Center Architecture
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`As shown in Figure 1-4, VMware Infrastructure presents a simple
`set of virtual elements used to build a virtual data center:
`• Computing and memory resources called Hosts, Clusters and
`Resource Pools
`• Storage resources called Datastores
`• Networking resources called Networks
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`VMware white paper
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`• Virtual machines
`A Host is the virtual representation of the computing and
`memory resources of a physical machine running ESX Server.
`When one or more physical machines are grouped together
`to work and be managed as a whole, the aggregate comput-
`ing and memory resources form a Cluster. Machines can be
`dynamically added or removed from a Cluster. Computing and
`memory resources from Hosts and Clusters can be finely parti-
`tioned into a hierarchy of Resource Pools.
`Datastores are virtual representations of combinations of
`underlying physical storage resources in the data center. These
`physical storage resources can come from the local SCSI disks of
`the server, the Fiber Channel SAN disk arrays, the iSCSI SAN disk
`arrays, or Network Attached Storage (NAS) arrays.
`Networks in the virtual environment connect virtual machines
`to each other or to the physical network outside of the virtual
`data center.
`Virtual machines are designated to a particular Host, Cluster
`or Resource Pool and a Datastore when they are created. A
`virtual machine consumes resources like a physical appliance
`consumes electricity. While in powered-off, suspended, or
`idle state, it consumes no resources. Once powered-on, it
`consumes resources dynamically, using more as the workload
`increases or give back resources dynamically as the workload
`decreases.
`Provisioning of virtual machines is much faster and easier
`than physical machines . New virtual machines can be created
`in seconds, no purchase order is required, no waiting, no
`physical constraints to worry about. Once a virtual machine is
`provisioned, the appropriate operating system and applications
`can be installed unaltered on the virtual machine to handle a
`particular workload just as though they were being installed on
`a physical machine. To make things easier, a virtual machine
`can even be provisioned with the operating system and appli-
`cations already installed and configured.
`Resources are provisioned to virtual machines based on
`the policies set by the system administrator who owns
`the resources . The policies can reserve a set of resources for
`a particular virtual machine to guarantee its performance. The
`policies can also prioritize and set a variable portion of the total
`resources to each virtual machine. A virtual machine will be
`prevented from being powered-on (to consume resources) if
`doing so would violate the resource allocation policies. For
`more information on resource management, please see the
`Resource Management Guide.
`The following sections examine in detail the virtual elements of
`the data center.
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`VMware white paper
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`Hosts, Clusters and resource Pools
`Hosts, Clusters and Resources Pools provide flexible and
`dynamic ways to organize the aggregated computing and
`memory resources in the virtual environment and link them
`back to the underlying physical resources.
`A Host represents the aggregate computing and memory
`resources of a physical x86 server. For example, if the physical
`x86 server has four dual-core CPUs running at 4 GHz each and
` GB of system memory, then the Host will have  GHz of
`computing power and  GBs of memory available for running
`virtual machines that are assigned to it.
`A Cluster represents the aggregate computing and memory
`resources of a group of physical x86 servers sharing the same
`network and storage arrays. For example, if the group contains
`8 servers, each server has 4 dual-core CPUs running at 4 GHz
`each and  GB of memory. The Cluster will then have 6 GHz
`of computing power and 6 GB of memory available for the
`running virtual machines assigned to it.
`The virtual resource owners do not need to be concerned with
`the physical composition (number servers, quantity and type
`of CPUs—Multi-core, Hyperthreading, etc) of the underlying
`Cluster to provision resources. They simply set up the resource
`provisioning policies based on the aggregate available resource.
`VMware Infrastructure will automatically assign the appropri-
`ate resources dynamically to the virtual machines within the
`boundaries of those policies.
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`Figure 1-5: Hosts, Clusters and Resource Pools
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`Finance Department
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`Accounting
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`Other
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`Payroll
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`4 GHz
`16 GB RAM
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`Figure 1- illustrates the concept of Resource Pools. Three x86
`servers with 4 GHz computing power and 16 GB of memory
`each are aggregated to form a Cluster of 1 GHz computing
`power and 48 GHz of memory. A Resource Pool (“Finance
`Department”) reserves 8 GHz computing power and  GBs
`of from the Cluster, leaving 4 GHz computing power and 16
`GBs of memory for the virtual machine “Others.” From the
`“Finance Department” Resource Pool, a smaller Resource Pool
`(“Accounting”) reserves 4 GHz computing power and 16 GBs
`for the virtual machines from the accounting department. That
`leaves 4 GHz and 16 GBs of memory for the virtual machine
`called “Payroll”. Resources reserved can be dynamically
`changed . Imagine that at year end, Accounting’s workload
`increases, the user wants to increase the Resource Pool
`“Accounting” from reserving 4 GHz of computing power to 6
`GHz. We can simply make the change to the Resource Pool
`dynamically without shutting down the associated virtual
`machines . Resources reserved for a Resource Pool or virtual
`machine are not taken away immediately. They dynamically
`respond to the demand. For example, if the 4 GHz of comput-
`ing resources reserved for the Accounting department are
`not being used, virtual machine “Payroll” can make use of the
`remaining processing capacity during its peak time. When
`Accounting again requires the processing capacity, “Payroll”
`will dynamically give them back. As a result, even though
`resources are reserved for different Resource Pools, they
`are not being wasted if not used by their owner .
`As demonstrated by the example, Resource Pools can be
`nested, organized hierarchically and dynamically reconfigured
`so that the IT environment matches the company organiza-
`tion. Individual business units can use dedicated infrastructure
`resources while still benefiting from the efficiency of resource
`pooling.
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`8 GHz
`32 GB RAM
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`Cluster
`12 GHz
`48 GB RAM
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`Resources Pools provide a flexible and dynamic way to divide
`and organize computing and memory resources from a Host or
`a Cluster. Any Resource Pools can be partitioned into smaller
`Resource Pools at a fine-grain level to further divide and assign
`resources to different groups or for different purposes.
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`6
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`VMware VMotion, VMware DrS and
`VMware Ha
`VMware VMotion, VMware DRS and VMware HA are distributed
`services that enable efficient and automated resource manage-
`ment and high virtual machine availability.
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`VMware VMotion
`As mentioned earlier, virtual machines run on and consume
`resources from individual physical x86 servers through VMware
`ESX Server. VMotion enables the migration of running virtual
`machines from one physical server to another without
`service interruption as shown in Figure 1-6. This allows virtual
`machines to move from a heavily loaded server to a lightly
`loaded one. The effect is a more efficient assignment of
`resources. Hence, with VMotion, resources can be dynamically
`reallocated to virtual machines across physical servers.
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`Figure 1-6: VMware VMotion
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`VMware DRS
`Taking the VMotion capability one step further by adding
`an intelligent scheduler, VMware DRS enables the system
`administrator to set resource assignment policies that
`reflect business needs and let VMware DRS do the cal-
`culation and automatically handle the detailed physical
`resource assignments . VMware DRS dynamically monitors
`the workload of the running virtual machines and the resource
`utilization of the physical servers within a Cluster. It checks
`those results against the resource assignment policies, if there
`is a potential for violation or improvement, it utilizes VMotion
`and dynamically reassigns virtual machines to different physical
`servers, as shown in Figure 1-, to ensure that the policies are
`complied and resource allocation is optimal.
`If a new physical server is made available, VMware DRS auto-
`matically redistributes the virtual machines to take advantage
`of it. Conversely, if a physical server needs to be taken down
`for any reason, VMware DRS redistributes its virtual machines
`to other servers automatically. For more information, see the
`VMware DRS white paper.
`
`VMware white paper
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`Figure 1-7: VMware DRS
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`VMware HA
`VMware HA offers a simple and low cost high availability
`alternative to application clustering . It enables quick restart
`of virtual machines on a different physical server within a
`Cluster automatically should the hosting server fail. All applica-
`tions within the virtual machines will benefit from high avail-
`ability, not just one as with application clustering.
`VMware HA works by placing an agent on each physical server
`to maintain a “heartbeat” with the other servers in the Cluster.
`As shown in Figure 1-8, loss of a “heartbeat” from one server
`automatically initiates the restarting of all affected virtual
`machines on other servers.
`Setting up VMware HA can be done simply by designating the
`priority order of virtual machines to be restarted in the Cluster.
`This is very simple when compared to the set up and configura-
`tion effort required for application clustering. Furthermore,
`even though VMware HA requires a certain amount of non-
`reserved resources to be maintained at all times to ensure that
`the remaining live servers can handle the total workload, it does
`not require doubling the amount of resources like application
`clustering. For more information, see the VMware HA
`white paper.
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`Figure 1-8 . VMware HA
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`or provide failover in the event of an adapter hardware
`failure . The failover is transparent to all virtual machines
`without the need to configure any of them specifically for
`NIC teaming. For information on NIC teaming, see the Server
`Configuration Guide.
`Port Group is a unique concept in the virtual environ-
`ment . A Port Group is a mechanism for setting policies
`that govern the network connected to it . A vSwitch can
`have multiple Port Groups. Instead of connecting to a particular
`port on the vSwitch, a virtual machine connects its vNIC to a
`Port Group. All virtual machines that connect to the same Port
`Group belong to the same network inside the virtual environ-
`ment even if they are on different physical servers as shown in
`Figure 1-9. Network C is the same on both Host1 and Host.
`Even if all other conditions are met, a virtual machine can
`VMotion from one physical server to another only if both
`servers have the same vSwitch (with the same Port Groups).
`The network connection is maintained after following the
`VMotion Migration because the virtual machine is automatically
`connected to the same Port Group on the same vSwitch on
`new hosting server.
`Port Groups can be configured to enforce a number of policies
`that provide enhanced networking security, network segmenta-
`tion, better performance, higher availability and traffic manage-
`ment:
`• Layer  security options can be set for a Port Group to isolate
`compromised or malicious virtual machines and prevent
`them from potentially doing harm to other machines in the
`network.
`• VLAN support can be configured for a Port Group to allow
`segmentation of the network
`• Specific NIC teaming policies can be set for an individual Port
`Group (Network) to share traffic load or provide failover in
`case of hardware failure
`• Traffic Shaping policies can be set to improve traffic manage-
`ment
`For more information on Port Group configuration, please see
`the Server Configuration Guide.
`
`VMware white paper
`
`Networking architecture
`VMware Infrastructure is the only solution that provides
`a rich set of virtual networking elements that makes net-
`working the virtual machines in the data center as easy and
`simple as in the physical environment. Furthermore, it enables
`a new set of capabilities not possible in the physical environ-
`ment because many of the limitations in the physical world
`don’t apply.
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`Figure 1-9: Networking Architecture
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`physical network
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`Figure 1-9 shows the relationship between the networks inside
`and outside the virtual environment. The virtual environment
`provides similar networking elements as the physical world.
`They are virtual network interface cards (vNIC), virtual switchs
`(vSwitch) and Port Groups.
`Like a physical machine, each virtual machine has its own
`vNICs. The operating system and applications talk to the vNICs
`through a standard networking device driver or a VMware
`optimized networking device driver just as though the vNIC
`is a physical NIC. To the outside world also, each vNIC appears
`just like a physical NIC – it has its own MAC address, one or
`more IP addresses and it responds to the standard Ethernet
`protocol exactly as a physical NIC would.
`A vSwitch works like a Layer  physical switch. Each physical
`server has its own vSwitches. On one side of the vSwitch are
`Port Groups which connect to virtual machines. On the other
`side are uplink connections to physical Ethernet adapters on
`the server where the vSwitch resides. Virtual machines connect
`to the outside world through the physical Ethernet adapters
`that are connected to the vSwitch uplinks.
`A virtual switch can connect its uplinks to more than one
`physical Ethernet adapter to enable NIC teaming two or
`more physical adapters used to share the traffic load
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`8
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`

`

`VMware white paper
`
`A Datastore is physically a VMFS file system volume or a direc-
`tory on a NAS device. Each Datastore can span multiple physical
`storage subsystems. As shown in Figure 1-10, a single VMFS
`volume can contain one or more LUNs from a direct attached
`SCSI disk array on a physical server, a Fiber Channel SAN disk
`farm, or iSCSI SAN disk farm. New LUNs added to any of the
`physical storage subsystems are automatically discovered and
`made available. They can be added to extend a previously
`created Datastore without powering down physical servers
`or storage subsystems. Conversely, if any of the LUNs within
`a Datastore fails or becomes unavailable, only those virtual
`machines that reside in that LUN are affected. All other virtual
`machines residing in other LUNs continue to function as
`normal.
`VMFS is a clustered file system that leverages shared storage to
`allow multiple physical servers to read and write to the same
`storage simultaneously. VMFS provides on-disk distributed
`locking to ensure that the same virtual machine is not powered
`on by multiple servers at the same time. If a physical server fails,
`the on-disk lock for each virtual machine can be released so
`that virtual machines can be restarted on other physical servers.
`VMFS also features enterprise class crash consistency and
`recovery mechanisms, such as distributed journaling, crash
`consistent virtual machine IO path, and machine state snap-
`shots. These mechanisms can aide quick root-cause analysis
`and recovery from virtual machine, physical server, and storage
`subsystem failures.
`VMFS also supports Raw Device Mapping (RDM). RDM provides
`a mechanism for a virtual machine to have direct access to a
`LUN on the physical storage subsystem (Fiber Channel or iSCSI
`only). RDM is useful for supporting two typical types of applica-
`tions:
`• SAN snapshot or other layered applications that run in the
`virtual machines. RDM better enables scalable backup offload-
`ing systems using features inherent to the SAN.
`• Any use of Microsoft Clustering Services (MSCS) spans
`physical servers: virtual-to-virtual clusters as well as physical-
`to-virtual clusters. Cluster data and quorum disks should be
`configured as RDMs rather than as files on a shared VMFS.
`
`Storage architecture
`The VMware Infrastructure enables enterprise-class storage
`performance, functionality and availability without adding
`complexity to the user applications and guest operating
`systems.
`The VMware Infrastructure Storage Architecture consists of
`layers of abstraction that hide and manage the complexity and
`differences between physical storage subsystems and present
`simple standard storage elements to the virtual environment
`(see Figure 1-10). To the applications and guest operating
`systems inside each virtual machine, storage is presented
`simply as SCSI disks connected to a virtual Bus Logic or LSI SCSI
`Host Bus Adapter.
`
`Figure 1-10: Storage Architecture
`
`host1
`
`VM1
`
`VM2
`
`host2
`
`VM3
`
`VM4
`
`datastore1
`
`vm1.vmx
`
`vm2.vmx
`
`vm3.vmx
`
`file1.vmdk
`
`file2.vmdk
`
`file3.vmdk
`
`VMFS volume
`
`datastore2
`
`vm4.vmx
`
`file4.vmdk
`
`NFS
`
`virtual
`
`physical
`
`IP network
`
`DAS SCSI
`
`FC SAN
`
`iSCSI
`
`NAS
`
`The virtual SCSI disks inside the virtual machines are provi-
`sioned from Datastore elements in the data center. A Datastore
`is like a storage appliance that serves up storage space for
`virtual disks inside the virtual machines as well as storing the
`virtual machines themselves. As shown in Figure 1-10, a virtual
`machine is stored as a set of files in its own directory in the
`Datastore. A virtual disk inside each virtual machine is located
`one or more files inside the directory. As a result, a virtual disk
`can be easily manipulated (copied, moved, backed-up, and
`so on) just like a file. Virtual disks can be “hot-added” to a
`virtual machine without powering it down . In which case,
`a new virtual disk file is created or an existing virtual disk file is
`associated with the virtual machine.
`The Datastore provides a simple model to allocate storage
`space for the individual virtual machines without exposing
`them to the complexity of the variety of physical storage tech-
`nologies available, such as Fiber Channel SAN, iSCSI SAN, Direct
`Attached Storage, and NAS.
`
`9
`
`

`

`VMware white paper
`
`Figure 1-11: Raw Device Mapping
`
`Figure 1-12: How Consolidated Backup Works
`
`host
`
`VM
`
`read/write
`
`open
`
`datastore
`
`Virtual Machines
`
`App
`
`OS
`
`App
`
`OS
`
`App
`
`OS
`
`ESX Server
`
`Backup Disk
`
`Tape
`
`OR
`
`Backup
`Proxy
`Server
`
`Centralized
`Data Mover
`
`mapping file
`
`VMFS volume
`
`virtual
`
`physical
`
`Physical Server
`
`SAN Storage
`
`LUN
`
`FC SAN
`or iSCSI SAN
`
`An RDM can be thought of as a symbolic link from a VMFS
`volume to a raw LUN (see Figure 1-11). The mapping makes
`LUNs appear as files in a VMFS volume. The mapping file—not
`the raw LUN—is referenced in the virtual machine configura-
`tion.
`When a LUN is opened for access, VMFS resolves the RDM file
`to the correct physical device and performs appropriate access
`checks and locking. Thereafter, reads and writes go directly to
`the raw LUN rather than going through the mapping file.
`
`VMware Consolidated Backup
`VMware Infrastructure’s storage architecture enables a simple
`virtual machine backup solution: VMware Consolidated Backup.
`Consolidated Backup provides an easy to use, centralized
`facility for agent-less backup of virtual machines . As shown
`in Figure 1-1, Consolidated Backup works in conjunction with
`a third-party backup agent residing on a separate backup
`proxy server (not on the server running ESX Server) but does
`not require an agent inside the virtual machines. The third-
`party backup agent manages the backup schedule. It starts
`Consolidated Backup when it is time to do a back up. Once
`started, Consolidated Backup runs a set of pre-backup scripts
`to quiesce the virtual disks to take their snapshots. It then runs
`a set of post-thaw scripts to restore the virtual machine back
`to normal operation. At the same time, it mounts the disk
`snapshot to the backup proxy server. Finally, the third-party
`backup agent backs up the files on the mounted snapshot to
`its backup targets. By taking snapshots of the virtual disks and
`backing them up at any time without worrying about backup
`windows or need to quiesce applications, Consolidated Backup
`provides a simple, less intrusive and low overhead backup
`solution for the virtual environment.
`
`eSX Server external Interfacing Components
`ESX Server is a virtualization layer that abstracts the processor,
`memory, storage, and networking resources of a physical server
`into multiple virtual machines that run side-by-side in a secured
`and isolated manner. There is one copy of the ESX Server that
`runs on each physical x86 machine. In this section, only the
`components of ESX Server that interfaces with the outside
`w