What's New in Windows 8 for Hyper-V Based Cloud Computing - Hyper-V Key Features

Part 1

In this article, you will learn about new key Hyper-V features in Windows Server 8.

The Multi-Tenant Cloud

At the Microsoft Build conference held September 13 – 16, 2011 in Anaheim, Microsoft provided a first look at Windows Server 8 features, including Hyper-V, which will enable organizations to support Infrastructure as a Service (IaaS) deployments using public, private and hybrid, multi-tenant cloud architectures. A multi-tenant cloud is a cloud infrastructure that is capable of hosting services (workloads) for multiple, distinct organizations (i.e., distinct departments within a single company in a private cloud, or distinct companies in a public cloud) while maintaining secure workload isolation amongst the various tenants. In addition, a multi-tenant cloud infrastructure is capable of dynamically placing and redistributing tenant workloads on any available host in the cloud without compromising the secure workload isolation. Finally, the multi-tenant cloud infrastructure must be able to provide and guarantee distinct Service Level Agreements (SLAs) that are based on organizational requirements, and provide resource metering that allows proper charge-back for the use of cloud resources to each organization. In order to enable multi-tenant cloud infrastructures, Windows Server 8 includes a slew of new features that span Hyper-V, storage, network, high-availability, disaster recovery, and manageability.

Hyper-V Core Features in Windows Server 8 

In Windows Server 8, Hyper-V features are enhanced, improving virtual machine performance and providing a scalable virtualization base for cloud deployments. Table 1 provides a comparison of Hyper-V key features between Windows Server 2008 R2 and Windows Server 8.

Hyper-V Features	Windows Server 2008 R2	Windows Server 8
Host Memory	1 TB	2 TB
Logical Processors	64 (Max)	160 (Max)
Guest VM Memory	64 GB (Max)	512 GB (Max)
Guest Virtual Processors	4 per VM (Max)	32 per VM (Max)
Guest NUMA	N	Y
Host Failover Cluster	Y (16 nodes)	Y (63 nodes)
VM Support - Failover Cluster	1000 (Max)	4000 (Max)
Live Migration	Y (serial)	Y (concurrent)
Live Migration (no cluster or shared storage)	N	Y
Live Storage Migration	N	Y

Table 1: Hyper-V Feature Comparison

Hyper-V now supports 2 TB of physical memory and a maximum of 160 logical processors. In Hyper-V, it is not only cores that are included in the logical processor count, so are threads if a core is Simultaneous Multi-Threading (SMT) enabled. Therefore, the following formula is handy to calculate the number of logical processors that Hyper-V can see on a given physical server:
# of Logical Processors = (# of Physical Processors) * (# of Cores) * (# of Threads per Core)
The increase in memory and logical processor support in Windows Server 8 provides the basis upon which to build dense virtual machine populations for private and public cloud infrastructures. In addition, Hyper-V in Windows Server 8 supports enhanced virtual machine performance by enabling the assignment of up to 512 GB of RAM and 32 virtual processors to a virtual machine. That can easily accommodate scale up of high-performing workloads especially coupled with intelligent resource management features like dynamic memory, and new networking and storage management features that you will discover later in this article.
For systems and applications that are built on top of a non-uniform memory access (NUMA) architecture, Windows Server 8 provides guest NUMA. Guest NUMA means that Hyper-V ensures guest virtual machine processor and memory affinity with physical host resources.
Another upgraded feature in Windows Server 8 is the expansion of failover clusters to 63 nodes (from 16 nodes in Windows Server 2008 R2), effectively quadrupling the size of a cluster and the number of running virtual machines to 4000 (from 1000 in Windows Server 2008 R2) per cluster.
With Windows Server 8, Hyper-V also supports multiple, concurrent live migrations of virtual machines. The number of concurrent live migrations is bounded only by the inherent resource constraints of the infrastructure rather than the serial limitation imposed in Hyper-V on Windows Server 2008 R2.
And while Live Migration has been a cluster-centric feature requiring shared storage, the story gets significantly better in Windows Server 8 with the support for live migration of a virtual machine between any two hosts without requiring clustering, shared storage, or any shared resources other than a network connection. You can control which Hyper-V hosts participate in this Live Migration mode, as well as the number of concurrent live migrations allowed by a host, and the network to use to perform the live migration. Furthermore, there is additional granularity in the selection of virtual machine components to migrate, allowing you to choose all components, including the VHD files, current configuration, snapshots, and second level paging, or only some of these components. You also have the ability to move the virtual machine data to a single location, or to specify individual locations for every selected virtual machine component.
As if all this goodness wasn’t enough, Hyper-V also provides Live Storage Migration that supports moving virtual machine storage resources between physical storage units without service interruption.

Hyper-V Key Storage Features in Windows Server 8

One of the main new Hyper-V storage features is the addition of a virtual Fibre Channel HBA adapter for virtual machines. This allows a virtual machine to connect to a Fibre Channel SAN, and enables new scenarios like guest clustering, use of MPIO, and other multipathing solutions for workloads that require high-performing SAN and application availability. This feature is available to existing Windows virtual machines like Windows Server 2008 R2 running on Hyper-V on Windows Server 8.
Another new storage feature is the VHDX format, a new virtual hard disk (VHD) format that is introduced in Windows Server 8. With VHDX, the maximum size of a VHD increases to 16 TB, instead of the current 2 TB limit with the current VHD format which forces the use of pass-through disks to meet larger virtual disk storage requirements. The VDHX format also provides large sector support, and allows embedding user-defined metadata.
Along with the increase in virtual disk size is an impressive performance boost when creating or managing large VHDX-based formats using the Offloaded Data Transfer (ODX) features of storage systems. Hyper-V support for ODX in Windows Server 8 allows handing off operations like data transfers and file creations to the storage system which can perform the actions with much higher performance while reducing the impact of associated operations on the Hyper-V host processor.

Hyper-V Key Network Features in Windows Server 8

On the networking side, one the of the key Hyper-V features in Windows Server 8 is the extensible Hyper-V switch. The Hyper-V switch is the component that controls the configuration and creation of external, internal, and private networks that support virtual machine connectivity to physical networks, to other virtual machines and the Hyper-V host, or to a subset of virtual machines, respectively. In Windows Server 2008 R2, the Hyper-V switch functionality cannot be modified. In Windows Server 8, an API exists that enables extension of the Hyper-V switch functionality. Microsoft’s goal is to enable security vendors to develop new security appliances as pluggable switch modules, enable switch vendors to create switch extensions that unify virtual and physical switch management, and enable network application vendors to create network monitoring extensions for the Hyper-V switch. Taking advantage of the Hyper-V switch extensibility, Cisco Systems has already announced support for Windows Server 8 Hyper-V with its Cisco Nexus 1000V switch.
Probably one of the most requested networking features included in Windows Server 8 and supported by Hyper-V is NIC teaming. Up through Windows Server 2008 R2, NIC teaming has only been available as a third-party option. Windows Server 8 provides native NIC teaming that is configurable at the host (parent partition) or virtual machine (guest partition) level in either load balancing or failover mode. As a bonus, this new NIC teaming feature even works across different vendor network adapters.

 

 

Windows Server 8 Hyper-V new features

At the recent Windows Server Workshop at the Microsoft campus in Redmond Washington Jeff Woolsey, Principle Program Manager Lead for Windows Virtualization in the Windows Server and Cloud division presented the new features in the next version of their Hyper-V virtualization platform. In the introduction to the workshop Jeffery Snover, Distinguished Engineer and the Lead Architect for the Windows Server Division made the bold statement that with Microsoft it’s the third release is where Microsoft really gets it right and with regard to what Microsoft demonstrated in the next version of Hyper-V this is definitely true. The upcoming Hyper-V 3.0 release that’s included in the next version of Windows Server has closed the technology gap with VMware’s vSphere.

Hyper-V 3.0 Scalability

The days when Hyper-V lagged behind VMware in terms of scalability are a thing of the past. The new Hyper-V 3.0 meets or exceeds all of the scalability marks that were previously VMware-only territory. Hyper-V 3.0 hosts support up to 160 logical processors (where a logical processor is either a core or a hyperthread) and up to 2 TB RAM. On the VM guest side, Hyper-V 3.0 guests will support up to 32 virtual CPUs with up to 512 GB RAM per VM. More subtle changes include support for guest NUMA where the guest VM has processor and memory affinity with the Hyper-V host resources. NUMA support is important for ensuring scalability increases as the number of available host processors increase.

Multiple Concurrent Live Migration and Storage Live Migration

Perhaps more important than the sheer scalability enhancements are the changes in Live Migration and the introduction of Storage Live Migration. Live Migration was introduced in Hyper-V 2.0 which came out with Windows Server 2008 R2. While it filled an important hole in the Hyper-V feature set it wasn’t up to par with the VMotion capability provided in vSphere. Live Migration was limited to a single Live Migration at a time while ESX Server was capable of performing multiple simultaneous VMotions. In addition, vSphere supported a similar feature called Storage VMotion which allowed a VM’s storage to be moved to new locations without incurring any downtime. Hyper-V 3.0 erases both of these advantages. Hyper-V 3.0 supports multiple concurrent Live Migrations. There are no limits to the number of concurrent Live Migrations that can take place with Hyper-V 3.0. In addition, Hyper-V 3.0 also provides full support for Storage Live Migration where a virtual machine’s files ( the configuration, virtual disk and snapshot files) can be moved to different storage locations without any interruption of end user connectivity to the guest VM.
Microsoft also threw in one additional twist that vSphere has never had. Hyper-V 3.0 has the ability to perform Live Migration and Storage Live Migration without the requirement of a shared storage on the backend. The removal of this requirement really helps bring the availability advantages of Live Migration to small and medium sized businesses that came afford a SAN or don’t want to deal with the complexities of a SAN. The ability to perform Live Migration without requiring shared storage really sets Hyper-V apart from vSphere and will definitely be a big draw – especially for SMBs that haven’t implemented virtualization yet.

VHDX, ODX, Virtual Fiber Channel & Boot from SAN

Another important enhancement with Hyper-V 3.0 was the introduction of a new virtual disk format called VHDX. The new VHDX format breaks the 2TB limit that was present in the older VHD format and pushes the maximum size of the virtual disk up to 16 TB per VHDX. The new format also provides improved performance, support for larger block sizes and is more resilient to corruption.
Hyper-V 3.0 also supports a feature called Offloaded Date Transfer (ODX). ODX enables Hyper-V to take advantage of the storage features of a backend shared storage subsystem. When performing file copies on an ODX enabled SAN the OS hands off all of the data transfer tasks to the SAN providing much high file copy performance with zero to minimal CPU utilization. There is no special ODX button. Instead ODX works in the backend. ODX requires the storage subsystem to support ODX.

Companies that use fiber channel SANs will appreciate the addition of the virtual Fiber Channel support in the Hyper-V guests. Hyper-V 3.0 guests can have up to four virtual fiber channel host bus adapters. The virtual HBAs appear in the VMs as devices very like virtual NICs and other virtual devices. Hyper-V VMs will also be able to boot from both fiber channel and iSCSI SANs.

Extensible Virtual Switch & NIC Teaming

In keeping par with the sweeping changes in Hyper-V’s compute capabilities and storage Microsoft also made a some of significant enhancements to Hyper-V’s networking capabilities. First, they updated the virtual switch that’s built into the Hyper-V hypervisor. The new virtual switch has a number of new capabilities multi-tenant capability as well as the ability to provide minimum and maximum bandwidth guarantees. In addition to these features the new virtual switch is also extensible. Microsoft provides a API that allows capture, filter and forwarding extensions. To ensure the high quality of these virtual switch extensions Microsoft will be initiating a Hyper-V virtual switch logo program.
Another overdue feature that will be a part of Windows Server 8 is the built-in ability to provide NIC teaming natively in the operating system. VMware’s ESX Server has provided NIC teaming for some time. Prior to Windows Server 8 you could only get NIC teaming for Windows via specialized NICs from Broadcom and Intel. The new NIC teaming works across heterogonous vendor NICs and can provide support for load balancing as well as failover.

The Magic Number 3

As Jeffery Snover pointed out three does seem to be the magic number – at least for Hyper-V. Hyper-V 3.0 brings Microsoft’s virtualization on par with VMware’s vSphere. Businesses that are just getting into to virtualization or those businesses that may be bulking at VMware’s latest price increases will find Hyper-V to be a very cost effective and highly competitive alternative.

http://www.windowsitpro.com/blog/michael-oteys-blog-21/virtualization/windows-server-8-hyperv-30-evens-odds-vsphere-140573