We’ve got some more goodies for you in Storage Spaces Direct with the Windows Server Technical Preview 5 release. The key updates are:
- Automatic Configuration
- Managing Storage Spaces Direct using Virtual Machine Manager
- Chassis and Rack Fault Tolerance
- Deployment with 3 servers
- Deployments with NVMe, SSD and HDD
To make deployment simpler, we have integrated storage pool and storage tier creation into Enable-ClusterS2D (Enable-ClusterStorageSpacesDirect). Storage Spaces Direct will automatically create a single storage pool with all eligible disk devices. Storage Spaces Direct will also automatically create storage tiers reflecting the storage configuration of the system.
If Storage Spaces Direct finds disk devices that are not eligible, it will list these devices along with the description of why they were not eligible. Examples of ineligible disk devices could be devices without proper media type (must be SSD or HDD), without proper bus type (must be SATA, SAS or NVMe), or disk devices with existing partitions.
Managing Storage Spaces Direct using Virtual Machine Manager
In Technical Preview 5, we are introducing new simple workflows within System Center Virtual Machine Manager (VMM) to deploy new clusters or bring existing clusters with Storage Spaces Direct enabled under its management.
Let’s take the example of creating a new cluster with the Storage Spaces Direct capability enabled. This can be achieved by simply checking the “Enable Storage Spaces Direct” option as part of the Create Hyper-V Cluster wizard!
Under the covers, VMM automates the steps of installing the relevant Windows Server roles, run cluster validation, installation and configuration of failover clustering, and of course enable storage features. Once this is complete, the storage resources are available, and you can create a storage pool, carve out volumes, and deploy VMs on the cluster.
If you want to use the cluster as a Scale-Out File Server, for a disaggregated configuration, you can use the already existing workflows.
Note: In Technical Preview 5, VMM does not support automatic creation of storage pool as part of the Enable Storage Spaces Direct workflow.
Chassis and Rack Fault Tolerance
By default, Storage Spaces Direct is fault tolerant to server failures. In Windows Server Technical Preview 5 it becomes possible to make Storage Spaces Direct fault tolerant to chassis or rack failures. Once you configured the fault domains and their server membership, Storage Spaces Direct will use this information during initial data placement, data rebalancing and data repair to ensure that the data is resilient to chassis or rack failures.
The chassis fault domain is really useful for when you have multiple servers inside a chassis with shared infrastructure like power supplies or networking. When you have multiple chassis, you can make Storage Spaces Direct resilient to an entire chassis failing by configuring the chassis fault domains. Similarly, the rack fault domain is useful to protect against power loss of a rack or top-of-rack switch failures.
Deployments with 3 Servers
Starting Windows Server 2016 Technical Preview 5, Storage Spaces Direct can be used in smaller deployments with only 3 servers.
Deployments with fewer than four servers, support only mirrored resiliency. Parity resiliency or multi-resiliency are not possible, since these resiliency types require a minimum of four servers. With 2-copy mirror the deployment is resilient to 1 node or 1 disk failure, and with 3-copy mirror the deployment is resilient to 1 node or 2 disk failures.
Deployments with NVMe, SSD and HDD
Previously Storage Spaces Direct used SSD + HDD and NVMe + SSD storage configurations. With Technical Preview 5 it is now possible to use three tiers of physical storage with NVMe, SSD and HDD. In this configuration the NVMe devices are used for caching and both the SSD and HDD are used for capacity. Storage Spaces Direct will automatically create a performance storage tier with mirror resiliency and SSD media type, as well as a capacity storage tier with parity resiliency and HDD media type. The user can create volumes purely from performance tier for best performance, purely from capacity tier for best efficiency and from both performance and capacity for balanced performance and capacity.
Storage Spaces Direct also enables all SSD storage configurations using SSD with good write endurance as caching devices, and read-optimized SSD for capacity devices.
With these enhancements, Storage Spaces Direct can be used in the following storage configurations:
- SSD + HDD
- NVMe + HDD
- NVMe + SSD
- SSD + SSD
- NVMe + SSD + HDD
I am really excited about these new capabilities for Storage Spaces Direct in Windows Server 2016 Technical Preview 5. I hope you are too. Let me know what you think.