Configuring Site Awareness with Multi-active Disaggregated Datacenters

In a previous blog,I discussed the introduction of site-aware Failover Clusters in Windows Server 2016. In this blog, I am going to walk through how you can configure site-awareness for your multi-active disaggregated datacenters. You can learn more about Software Defined Storage and the advantages of a disaggregated datacenter here.

Consider the following multi-active datacenters, with a compute and a storage cluster, stretched across two datacenters. Each cluster has two nodes on each datacenter.

To configure site-awareness for the stretched compute and storage clusters proceed as follows:

Compute Stretch Cluster

1)     Assign the nodes in the cluster to one of the two datacenters (sites).

  • Open PowerShell© as an Administrator and type:
(Get-ClusterNode Node1).Site = 1
(Get-ClusterNode Node2).Site = 1
(Get-ClusterNode Node3).Site = 2
(Get-ClusterNode Node4).Site = 2

2)     Configure the site for your primary datacenter.

(Get-Cluster).PreferredSite = 1

Storage Stretch Cluster

In multi-active disaggregated datacenters, the storage stretch cluster hosts a Scale-Out File Server (SoFS). For optimal performance, it should be ensured that the site hosting the Cluster Shared Volumes comprising the SoFS, follows the site hosting the compute workload. This avoids the cost of cross-datacenter network traffic.

1)     As in the case of the compute cluster assign the nodes in the storage cluster to one of the two datacenters (sites).

(Get-ClusterNode Node5).Site = 1
(Get-ClusterNode Node6).Site = 1
(Get-ClusterNode Node7).Site = 2
(Get-ClusterNode Node8).Site = 2

2)     For each Cluster Shared Volume (CSV) in the cluster, configure the preferred site for the CSV group to be the same as the preferred site for the Compute Cluster.

$csv1 = Get-ClusterSharedVolume "Cluster Disk 1" | Get-ClusterGroup
($csv1).PreferredSite = 1 

3)  Set each CSV group in the cluster to automatically failback to the preferred site when it is available after a datacenter outage.

($csv1).AutoFailbackType = 1

Note: Step 2 and 3 can also be used to configure the Preferred Site for a CSV group in a hyper-converged data-center deployment. You can learn more about hyper-converged deployments in Windows Server 2016 here.