Reference Guide

The following figure shows an Active-Active setup:
Figure 1. An Active-Active setup
Sites can be logical or physical. For logical sites, a stretched cluster can exist on single or multiple racks or in different rooms
in the same data center. For physical sites, the stretched cluster can be in different data centers on the same campus or in
different cities or regions. Stretched clusters using two physical sites provide disaster recovery and business continuity should a
site suffer an outage.
Solution integration and network architecture
Dell EMC Solutions for Azure Stack HCI stretched clusters offer distinct network topologies that are validated with the
following stretched cluster configurations:
● Basic configuration
● High throughput configuration
Basic configuration refers to a network topology that requires minimal changes to a traditional single-site Azure Stack
HCI configuration. This configuration uses a single network/fabric for management, VM, and replication traffic, keeping host
networking simple. The customer network team must configure quality of service (QoS) on an external firewall or routers to
throttle inter-site bandwidth and thereby ensure that Replica/VM traffic does not saturate the Management network.
High throughput configuration suits customer environments that are dense and involves higher write IOPs compared to
a basic configuration. This configuration requires a dedicated channel (network interface cards (NICs) or fabric) for Replica
traffic (using SMB-Multichannel). This network topology should be used only if inter-site bandwidth is higher than 10 Gbps. The
network team must configure multiple static routes on the host to ensure that Replica traffic uses the dedicated channel that
has been created for it. If the customer environment does not use Border Gateway Protocol (BGP) at the ToR layer, static
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Solution overview