Introduciton
Cloud computing is the new way of approaching how to design and manage a data center. Some think the “private” in private cloud means it’s basically the same as any private data center, just renamed, but that’s a short-sighted view. What’s the difference, then? In contrast to the traditional approach to the data center, the cloud is about five key capabilities:
- Self-service. Users can obtain services from the cloud without interacting directly with IT.
- Broad network access. Services can be accessed by almost any device, from virtually anywhere, from all form factors.
- Elastic provisioning and deprovisioning. This enables the cloud to automatically provision resources for customers of the cloud and then return those resources to the cloud when no longer in use.
- Abstracted, pooled resources. Resources are abstracted from the user and the user obtains resources from a resource pool, which is typically shared throughout the entire cloud infrastructure.
- Metering. The cloud tracks resource utilization and reports back to the consumer of the cloud service, so that chargeback can be enabled if so desired.
Okay, those are the characteristics that define a cloud environment. In general, there are two ways to deliver cloud services (there are also other terms such as hybrid cloud, but we’re going to focus on these two):
- Public cloud. The public cloud is shared by tenants from multiple and often unrelated organizations.
- Private cloud. The private cloud is dedicated to a single organization, and may be shared by multiple divisions within that organization.
Within a cloud infrastructure, there are three service models:
- Infrastructure as a Service (IaaS). The cloud provider make infrastructure available to consumers of the service. The cloud service provider enables consumers of the cloud service to obtain networking, compute, memory and storage and do with that resources whatever they like to do.
- Platform as a Service (PaaS). The cloud provider provides operating systems and development platform where the consumer of the cloud service can deploy their applications. The infrastructure is completely transparent to the consumer.
- Software as a Service (SaaS). The cloud provider provides “finished services”, which is software that the consumer can use immediately to get the work done. The platform and infrastructure are completely transparent to the user.
Most organizations are likely to start the journey to the cloud by trying to set up a private cloud Infrastructure as a Service solution. IaaS can significantly improve a company’s agility and enable the organization to develop, test and deploy applications faster than ever before. And although the upfront costs might be relatively high, in the long run, the high level of automation and self-service can lead to significant cost saving.
Windows 8 Enables Private Cloud IaaS
So where does Windows 8 enter this picture? There are three major areas where Microsoft is designing Windows 8 to improvean organization’s ability to deliver an enterprise grade, highly robust datacenter:
- Improvements in the ability to scale the data center
- Improvements in high availability and data protection
- Improvements in networking and storage capabilities
Let’s take a quick look at what Windows 8 is expected to offer in each of these areas.
Scaling the Private Cloud to Provide a Perception of Infinite Capacity
One of the core features of cloud computing, whether public or private, is to create the perception of infinite capacity, so that users can obtain the resources they need, when they need them, without having to be concerned about whether adequate resources are available. Toward that end, Windows 8 includes the following features to help you increase your ability to scale so that you can move toward the perception of infinite capacity:
Support for Multi-Core Server
Windows Server 8 will support more than 64 processors per server. In fact, each individual VM will be able to support 32 processors.
Network Receive Side Scaling
Receive Side Scaling (RSS) allows multiple processors to be used to handle network related interrupts. That allows you to speed your networking because you won’t be bound to a single processor having to do all that work. Windows 8 will automatically detect whether the NIC supports this feature.
Network Receive Segment Coalescing
Receive Segment Coalescing (RCS) is able to collect packets that are received during the same interrupt cycle and put them together so that they can be more efficiently delivered to the network stack. This can significantly increase the amount of traffic that be handled without severely impacting the CPU.
Storage copy offload
Storage copy offload allows the storage device to do a file copy operation without requiring the machine that made the request to read the content between locations. This requires that the storage devices understand storage copy offload. When enabled, the Hyper-V host doesn’t have to do the work of copy operation and leaves it to the storage devices.
Server Message Block 2.0 Direct and Remote Direct Memory Access
Remote Direct Memory Access (Remote DMA) enabled NICs can offload network processing away from the processor and move it to the NIC. When paired with SMB 2 file shares, you can see performance with SMB 2.0 files shares that are comparable to what you see with Fibre channel SANs. This is a key feature that enables you to do live migration of VMs that are stored on file shares and not impact the processor, so that the processor can be used to service the workloads handled by the VMs.
Single Root I/O Virtualization
Single Root I/O enables you to configure a VM network interface so that it will be associated directly with the physical NIC. This reduces the overhead as the host virtualization stack doesn’t have to handle this activity, essentially bypassing the host system’s networking stack. This also enables you to optimize performance for live migrations of running services.
High Availability and Data Protection
A private cloud infrastructure must be highly available and must have a solid design to protect the data contained with the infrastructure. While we’re used to doing this in our traditional data centers, the private cloud takes these capabilities to the next level because the focus is on service delivery, not just “uptime”.
The following Windows 8 features and capabilities enable us to reach the optimum levels of HA and DP.
Out of the Box NIC Load Balancing and Failover
In your current data center, you’re likely using NIC teaming to team two NICs to support each other for failover. If one of the NIC fails, the other one takes up the slack. The problem is that historically, support for NIC teaming was spotty, and the level of support varied with the drivers that were provided by the NIC vendor. This meant that the NICs had to come from the same vendor and often were even required to be the same model.
In Windows 8, you no longer are limited to using NICs from the same vendor. In fact, the NICs don’t even have to be the same speed or have identical capabilities. Windows 8 will include, out of the box, support for NIC teaming. That means if you have a Broadcom NIC on the motherboard, and an Intel multiple port NIC in a PCI slot, you can team them. And because NIC teaming is part of the OS, you get support from Microsoft and don’t have to deal with finger pointing between vendors. It also means that Microsoft workloads will have to work with NIC teaming.
And remember, not only is failover supported, but so is network bandwidth aggregation. This allows you to squeeze even more bandwidth out of your services so that you can test the limits of your 100 Gbps switches in the future.
Incremental Backups for VHDs
Everyone knows the value of incremental backups. And everyone knows the value of incremental backups that are done over the network. In the past, you may have backed up the virtual machines in your environment by copying over the entire VM each time you performed a backup. Given the size of typical VMs, this consumes a ton of network bandwidth that is then no longer available to other workloads.
With Windows Server 8, you will be able to do incremental backups of your VHDs. This will significantly reduce the amount of bandwidth that’s required to make sure your virtual machines are protected. In addition, these backups are VSS aware, so you can continue running the workloads on the VMs while they are being backed up.
VM Replication with Hyper-V Replica
Disaster recovery is a key to a successful private cloud. The private cloud should make disaster recovery much simpler than what you might have in your current data center. This is where the new Hyper-V Replica feature comes in. This will enable easy and fast VM replication and recovery from disaster.
This feature will make it extremely easy for you to configure VMs to automatically replicate themselves to another Hyper-V server. The server can be another one on the same rack, or it might be in another building on campus, it might be one located at one of your data centers on another continent, or it might be somewhere in a hosted private cloud facility.
This redundancy makes it possible, in the event of a disaster, to quickly turn on the replicated VMs that are stored in the alternate locations. This feature will make it easier and faster than ever to get up and running again after a minor or major disaster.
Improvements in Private Cloud Networking and Storage
Private clouds will need to be optimized in order to get the most out of the networking and storage components of the infrastructure. To this end, Windows Server 8 will includethe following features:
Data Center Bridging (DCB) and OS-level Packet Scheduling
Microsoft currently recommends a high level of segmentation of the networking infrastructure to support isolation of workloads among the VMs and from the host. In a large private cloud deployment, this can lead to a high number of VLANs. The problem is that there is a limit to the number of VLANs you can configure, and the number is small enough that it doesn’t support the large scale required for private clouds.
Windows Server 8 includes improvements that will support new converged network designs, so that you can get the most out of the 10 Gbps second NICs installed on modern private cloud infrastructure servers. Windows Server 8 will also support strong Quality of Service (QoS), so that workload traffic is prioritized in a way that is consistent with the level of service you expose in your service catalog.
This also works with new Data Center Bridging (DCB) capable hardware, which makes it possible to use a single ultra-high bandwidth NIC and provide QoS and isolation services to support multi-tenant workloads expected on private cloud deployments.
Run Virtual Machines over the Network with SMB 2.0
This is one of my favorites. Why should we all go broke spending money on expensive storage arrays? Why not make it possible to have high performance storage using an SMB share? Well, apparently the Windows 8 designers at Microsoft asked themselves the same question and decided there’s no reason at all. What that means is that with Windows Server 8, you’ll be able to host your VHDs on SMB shares anywhere on your network. This capability is enabled by Remote DMA capable NICs. Now you can create private cloud Hyper-V arrays that use low cost, high performance file servers for storage at the fraction of the cost.
Storage Virtualization with Storage Spaces
Windows Server 8 Storage Spaces enables you to virtualize your storage so that it will become much easier to manage. This is an important feature in your private cloud, since storage must be abstracted as much as possible so that you can deliver storage as a menu item in your private cloud services catalog. Storage spaces can take advantage of garden variety file servers with commodity storage media and can have a profound effect on your bottom line.
Increase Usable Storage Space with Out of the Box De-Duplication
Here is another of my favorites: out of the box de-duplication. Windows Server 8 will segment data in 32-128KB chunks, looking for chunks that are the same, then maintain a single copy of the duplicated chunks while putting a token in the place of the chunk in the original location. Not only that, but the chunks will be compressed, saving even more space.
Summary
In this article, we introduced a number of new features and capabilities included with the upcoming Windows Server 8 operating system. All of these features are targeted at making Windows Server 8 the platform of choice for your virtualized private cloud infrastructure. From what I can tell, it looks as if Microsoft is going to leapfrog other vendors in terms of feature support for enterprise requirements for a private cloud Infrastructure as a Service offering. In future articles, we’ll do deeper dives into some of these technologies and provide you with specifics on how to use them.
