With a lot of new features and changes, there was a big focus on Windows Server storage in 2012 R2. The latest...
version of Windows Server improves performance flexibility, efficiency and performance with new tools, like native tiered storage and Storage Spaces. These changes will help administrators keep costs down and boost storage performance -- if they know how to use them. Here are five frequently asked questions about the new storage changes in Windows Server 2012 R2.
What is a Generation 2 virtual machine?
A Generation 2 VM is a new feature in Windows Server Hyper-V 2012 R2 that takes the current virtual machine structure and attempts to modernize it by allowing the VM to run more efficiently.
Generation 2 VMs are now hypervisor aware, meaning they no longer have to rely on emulated or synthetic hardware. They also use virtual SCSI disks as a default instead of Integrated Drive Electronics, or IDE, disks. Virtual SCSI disks were an option for first-generation VMs, but it is now the default option and makes it easier to create and attach numerous virtual hard disks to a VM.
There are some negatives to a Generation 2 VM as well. A Generation 2 VM cannot access physical DVD drives. They also can host only 64-bit editions of Windows Server 2012 R2, and these VMs can't be live-migrated to a host running a previous version of Windows Server.
How does the shared VHDX file feature work?
A shared VHDX file works by creating a virtual hard disk and sharing it among multiple VMs, and is intended for use with guest clustering. Although shared VHDX files do not eliminate the need for physical shared storage, they allow administrators to keep their storage infrastructure more private, and can be shared among guest cluster nodes as if they were an actual Cluster Shared Volume.
What is the native tiered storage feature and how can it help?
Windows Server 2012 R2 came loaded with a lot of new storage features, and the native tiered storage feature is one of the biggest improvements. Native tiered storage will differentiate between solid-state drives (SSDs) and hard disk drives (HDDs) which will boost the read performance on the server. With native tiered storage, Windows will move the files that are needed more frequently to SSDs, which are faster, while files that aren't accessed as frequently will be placed on HDDs. Another perk of the native tiered storage feature is how simple it is to implement.
What is storage QoS?
Native tiered storage received a lot of the spotlight, but another feature, storage QoS, is just as significant. Storage QoS will play a big role in controlling disk I/O, a traditional problem for administrators. Storage QoS allows administrators to set limits and reservations on storage IOPS per virtual hard disk (VHD). Even if a single VM is connected to multiple VHDs, storage QoS makes it possible to set limits per VHD.
What are Storage Spaces' capabilities in Windows Server 2012 R2?
There's more than just basic storage support for Windows Server 2012 R2's Storage Spaces, as it also protects data and uses snapshots, among other things. One of the biggest improvements in this version is that it supports data duplication, which boosts performance. Dual parity helps administrators recover quickly, because the disk is rebuilt using spare capacity storage, which limits the effect on the storage performance. Tiered storage, as answered above, helps to store data based on how frequently it's needed, and write-back cache helps reduce I/O traffic.