Reference Guide

Creating a stretched cluster

This chapter presents the following topics:

Topics:

• Introduction

• Test-Cluster

• Cluster creation

• Volumes

• Storage efficiency

• Test-SRTopology

Introduction

This section outlines the steps that are needed for configuring a stretched cluster. Complete the network configuration on

all nodes for the network topology applicable to you. A sample IP address schema is provided for both supported network

topologies in the previous section of this guide. Consider these points before you begin:

● Ensure management IPs of all nodes are reachable from any host

● Ensure static routes are configured on all hosts for inter-site communication using the Replica network

● Ensure all nodes from Site A can reach corresponding Replica IPs on Site B using the Replica path

Test-Cluster

Test-Cluster is a fundamental function that is needed to ensure that the cluster to be created meets Microsoft's

recommendations regarding Failover Clustering. It also ensures that your hardware and settings are compatible. Run Test-

Cluster with all nodes and include All Tests (namely, 'Storage Spaces Direct', 'Inventory', 'Network' and 'System Configuration').

Ensure there are test-cluster passes without warnings for the 'High Throughput Configuration', while 'Basic Configuration' will

receive a warning as mentioned in the previous section of this guide.

Cluster creation

This section looks at creating a cluster using PowerShell cmdlets.

Manual cluster creation

Once Test-Cluster completes successfully, use the New-Cluster cmdlet to create a new stretched cluster. Because the nodes

specified are part of different IP schemas, Enable-ClusterS2D understands that the cluster is part of a multi-site topology. It

automatically creates two storage pools and corresponding ClusterPerformanceHistory volumes and their replica volumes.

After a cluster is created, you will see a warning similar to the one shown below. This is an expected behavior.

No matching network interface found for resource 'Cluster IP Address 172.18.160.160' IP

address '192.168.200.100' (return code was '5035'). If your cluster nodes span different

subnets, this may be normal.

Configure cluster witness and Enable Storage Spaces Direct on the cluster.

NOTE:

Cluster witness can be either on a tertiary site or on Azure Cloud. Ensure that the "Storage Replica" feature is

installed on all nodes in the cluster.

14 Creating a stretched cluster