What is new in Failover Clustering in Windows Server 2016

Finally, I’d like to review what’s new in failover clustering in Windows Server 2016. Actually, I wrote this article a couple of months ago for Russian official Microsoft blog so if you are Russian you can go to this resource to read it in your native language.

Also, I described some of the new features before RTM-version (when only TPs were available) and almost all of them can be applied to Windows Server 2016 as well. It means there are no significant changes in RTM for them. I’ll provide a short description of such features and links to my previous posts with a detailed information.

And yes, of course, completely new functionality (Load Balancing, for instance) will also be described here

I have all of this in PDF format. Ping me in the comments/email and I’ll send to you the copy PDF has been shared 

Cluster OS Rolling upgrade

Cluster migration is usually a headache for administrators. It could be the reason of huge downtime (because we need to evict some nodes from old cluster, build the new one based on these nodes or new hardware and migrate roles from source cluster. So, in the case of overcommitment we won’t have enough resources to run migrated VMs). It’s critical for CSPs and other customers that have implemented SLA policy.

Windows Server 2016 fixes this by adding possibility to place Windows Server 2012 R2 and Windows Server 2016 nodes in the same cluster during upgrade/migration phase.

The new feature named as Cluster Rolling Upgrade (CRU) significantly simplifies overall process and allows us to successively upgrade existed nodes without destroying cluster. It helps to reduce downtime and any required costs (hardware, staff time and etc.)

Cluster Rolling Upgrade Windows Server 2016

The full list of CRU benefits is listed below:

  • Hyper-V virtual machine and Scale-out File Server workloads can be upgraded ONLY from Windows Server 2012 R2 to Windows Server 2016 without any downtime. Other cluster workloads will be unavailable during the time it takes to failover (for example, SQL Server with AlwaysOn FCI ~ 5 minutes of downtime)
  • It does not require any additional hardware (for example, you evicted 1 node of 4. The rest 3 nodes are online and they must have resources for workloads live migrated from evicted node. In this case zero-downtime is predicted)
  • The cluster does not need to be stopped or restarted.
  • In-Place OS upgrade is supported BUT Clean OS install is highly recommended. Use In-Place upgrading carefully and always check logs/services before adding node back to cluster.
  • A new cluster is not required. In addition, existing cluster objects stored in Active Directory are used.
  • The upgrade process is reversible until the customer crosses the “point-of-no-return”, when all cluster nodes are running Windows Server Technical Preview, and when the Update-ClusterFunctionalLevel PowerShell cmdlet is run.
  • The cluster can support patching and maintenance operations while running in the mixed-OS mode.
  • CRU is supported by VMM 2016 and can be automated through PowerShell/WMI

To get more details read my previous post that shows CRU in action (it’s been written for Technical Preview but can still be used with RTM)

Hint: get list of supported VM’s version by host (Get-VMHostSupportedVersion).

Supported VMs Version by Hyper-V Host

Cloud Witness

Failover cluster in Windows Server 2012 R2 can be deployed with an external disk or file share witness which must be available for each cluster nodes and it’s needed as a source of extra vote. As you may know, witness is highly recommended (I’d say it’s required!) for Windows Server 2012 R2 cluster regardless of a number nodes in it (dynamic quorum automatically decides when to use witness).

In Windows Server 2016 a new witness type has been introduced – Cloud Witness. Yes, it’s Azure-based and it’s specially created for DR-scenarios, Workgroup/Multi-Domain cluster (will be described later), guest clusters and clusters without shared storage between nodes.

Cloud Witness uses Azure Storage resources (Azure Blog Storage through HTTPS protocol. HTTPS port should be opened on all cluster nodes) for read/write operations. Same storage account can be used for different clusters because Azure creates a blob-file generated for each cluster with unique IDs. These blob-files are kept in msft-cloud-witness container and require just KBs of storage. So, costs are minimal and Cloud Witness can be simply used as a third site (“arbitration’) in stretched clusters and DR solutions.

Cloud Witness in Windows Server 2016

Cloud Witness scenarios:

  • Multi-Site clusters
  • Clusters without shared storage (Exchange DAG, SQL Always-On and etc.)
  • Guests clusters running on Azure and On-Premises
  • Storage Cluster with or without shared storage (SOFS)
  • WorkGroup and Multi-Domain Clusters (new in WS2016. It’ll be described later)

Continue reading “What is new in Failover Clustering in Windows Server 2016”

Windows Server 2016 Licensing and Pricing

Here are the some key points  from recently published licensing guides (may be updated in future with some changes):

Windows Server 2016 Pricing and Licensing FAQ (December, 2015)

Windows Server 2016 Licensing Datasheet (December, 2015)

  • WS 2016 Datacenter Edition for highly virtualized private and hybrid cloud environments.
  • WS 2016 Standard Edition for non-virtualized or lightly virtualized environments.
  • Other editions will also be available with more information coming in 2016.
  • The licensing of Windows Server 2016 Standard and Datacenter editions will shift to be based on physical cores from the prior licensing model based on processors. So licensing model for Standard and Datacenter will be Cores + CAL
  • Standard and Datacenter editions don’t have the same list of features as we have in Windows Server 2012/2012R2 (except AVMA ). Storage Replica , Storage Spaces Direct , Shielded VMs and New Networking stack are available only in Datacenter
  • [VOTE] Storage Replica and Storage Spaces Direct Were Killed By Licensing

windows server 2016 licensing and pricing

Cores + CAL licensing model

To license a physical server, all physical cores must be licensed in the server. A minimum of 8 core licenses is required for each physical processor in the server and a minimum of 16 cores is required to be licensed for servers with one processor.

  • The price of 16-core licenses of Windows Server 2016 Datacenter and Standard Edition will be same price as the 2 proc license of the corresponding editions of the Windows Server 2012 R2 version.
  • Standard Edition provides rights for up to 2 OSEs or Hyper-V containers when all physical cores in the server are licensed.
  • Multiple licenses can be assigned to the same cores for additional OSEs or Hyper-V containers.
  • Each user and/or device accessing a licensed Windows Server Standard or Datacenter edition requires a Windows Server CAL.
  • Each Window Server CAL allows access to multiple licenses Windows Servers.
  •  A Windows Server CAL gives a user or device the right to access any edition of Windows Server of the same or earlier version.
  • Some additional or advanced functionality such as Remote Desktop Services or Active Directory Rights Management Services will continue to require the purchase of an additive CAL.

How to license:

  • License all the physical cores in the server
  • Minimum of 8 core licenses required for each proc
  •  Minimum of 16 core licenses required for each server
  • Core licenses will be sold in packs of two*

windows server 2016 licensing and pricing_2*8 two-core packs will be the minimum required to license each physical server. The two-core pack for each edition is 1/8th the price of a two proc license for corresponding 2012 R2 editions

How should I think about hyper-threading in the core based licensing?

Windows Server and System Center 2016 are licensed by physical cores, not virtual cores. Therefore, customers only need to inventory and license the physical cores on their processors.

If processors (and therefore cores) are disabled from Windows use, do I still need to license the cores?

If the processor is disabled for use by Windows, the cores on that processor do not need to be licensed. For example, if 2 processors in a 4 processor server (with 8 cores per processor) were disabled and not available for Windows Server use, only 16 cores would need to be licensed. However, disabling hyper threading or disabling cores for specific programs does not relieve the need for a Windows Server license on the physical cores.

Where is the information about other editions of Windows Server, Windows Storage Server, Azure Stack and other products coming next year?

More information is coming in Q1CY16 about Azure Stack, Windows Server Essentials and the rest of the Windows Server editions and other related products.

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