What's new in Windows Server 2012

Windows Server 2012 – "Cloud OS" as Microsoft sometimes refers to it, and "WS2012" as we'll call it for short – is the result of the deepest and broadest developer effort in the history of Microsoft server products: 10,000 engineers working for four years. Comments from testers and early adopters have included "jaw-dropping", "game-changing" and "the competitors better watch out".

As Jeff Woolsey, Microsoft's Principal Program Manager Lead, put it at the Technical Launch event in Hammersmith in London: "There are so many new features that I can't tell you. There are not enough hours in a day to describe them all. There are hundreds." Inevitably, all we can give you here is an overview.

Many of the new features relate to virtualisation and related areas, such as building and managing farms of virtual servers, including Windows Azure cloud servers, but even if you don't use virtualisation, there are enough other refinements to engage your interest.

As with its desktop cousin Windows 8, an important area of change concerns the user interface. Yes, WS2012 has no Start button or menu and instead has the same full-screen widget-based Start screen as the desktop version – but that's trivial. The important changes are invisible.

PowerShell

Although WS2012 still has NT's familiar CMD.EXE, its newer replacement, PowerShell, has received a very substantial revamp. PowerShell 3 has some 2,400 new "commandlets", up from about 200 in Windows Server 2008. Even if you're using the GUI tools, just about every aspect of the system can be controlled and configured using PowerShell 3.

All the administrative tools emit Powershell commands in the background, and both GUI and typed commands are stored in the Powershell history, so you can call them up, inspect them, copy and paste them into the new Powershell editor, modify them and keep them for future use.

Combined with auto-completion both in the shell and editor, it's a good way to explore and learn the shell. There are multiple ways to type most commands, too – most of the old DOS-style commands still work, and there are abbreviated Unix-style versions as well.

The Server Core desktopless (suggest using GUI-less) installation has been improved, too. A new, intermediate form of Server Core has enough GUI to run the PowerShell editor, but more importantly, a fully-installed server can be switched from the full desktop to Server Core and back again. Virtually everything can be configured remotely via the much improved Server Manager, anyway, either from another system – including a Windows 8 workstation with the admin toolkit installed – or from the host hypervisor.

Server Manager can now handle whole farms of machines, listing functions by role rather than on a per-machine basis. Most aspects of a machine can be configured through it, even low-level things like NIC teaming – so there's much less reason to actually open a session on a remote machine.

Resilient File System

Even if you never touch PowerShell, there are other benefits. The new Resilient File System, ResFS for short, is designed to be more robust than even NTFS against corruption or media failure – for instance, it does not re-use the same disk blocks again during a write, so if it's interrupted, the original data will be intact.

CHKDSK is much faster and can even be run with disks online. Sparse provisioning means that formatting new disks is vastly quicker, too – terabytes can be ready for use in seconds, a particularly big help when creating large, i.e, 64TB VHDx for VMs (virtual machines).

Automatic data deduplication is another handy tool – it scans disks and files and replaces duplicated data with links, so that the exact same contents take up much less space – in a demo, it saved 11GB on a disk containing three copies of a 5GB set of files. You can even copy the "ddpeval.exe" program from a WS2012 machine into \WINDOWS\SYSTEM32 on an older Windows Server and see how much space you'd save.

The fileserver component has seen a major revamp. The wire protocol has been streamlined and lots of "chatter" removed to make it faster over slower connections. On local networks, it supports multiple connections – for instance, even in mid-copy, plugging in a Gigabit cable will result in the time remaining dropping sharply.

IIS 8 has refinements such as CPU throttling, script pre-compilation, an improved FTP server and centralised SSL certificate management.

Hyper-V

The biggest changes are around the hypervisor and various aspects of virtualisation – and to a lesser extent, remote-desktop servers. WS2012 includes the third release of Hyper-V – now a mature, stable hypervisor, boasting a feature set to seriously worry VMware. Hosts, clusters and VMs all support industry-leading high-end specs and a swath of high-availability features. If you have a SAN, VMs now support virtual Fibre Channel ports for direct connections, and the fileserver role supports ODX for offloading operations onto SAN servers.

You don't need a SAN, though. VHDs can be stored on a file share, facilitating live migration between hosts even without a cluster, and the new Hyper-V Replica feature allows VMs to be replicated in the background between shared-nothing hosts, even across WAN links.

WS2012 also virtualises storage and networking. VM networking now goes through a full managed virtual switch, allowing network connections to be virtualised – so for example IP addresses can be reassigned on the fly from a VM on one machine to another on a different host, reducing the need for complex VLAN configurations.

The new storage pool system essentially brings full logical volume management to Windows, rivalling Sun's ZFS, with configurable mirroring and parity – so that all the storage attached or assigned to a server can be presented as a single pool, with flexible dynamic suballocation.

Microsoft now recommends that all servers run virtualised – even Domain Controllers; the new "Generation ID" flag in ActiveDirectory makes it simple to clone or roll-back a virtualised DC, which can then reconfigure itself appropriately. This need not cost more – although it's mainly meant for VDI and Linux virtualisation, the freeware Hyper-V Server can be used to host a full WS2012 instance.

VDI and Terminal Server functionality are both much improved, with features such as server GPU acceleration – and emulation if one isn't available – and enhanced RemoteFX for touch interfaces and better support for operation over the public Internet. VDI images can be either pooled or personalised, or pooled images can have a personal disk attached for seamless, local-disk-performance roaming profiles.

Even the licensing has been simplified – there are now only Standard and Datacenter editions, plus a forthcoming Essentials edition, the replacement for Small Business Server.

And of course much of this can also be applied to Azure cloud servers, which run the same code and can be administered with the same tools. Local server images can even be migrated into the Azure cloud.

Windows Server is all grown up: and with its enhanced virtualisation capabilities, it is ready to take on Linux in the cloud and VMware in the server room. ®

Windows Server 2012 - three videos