It’s Time to Expect Flexible Disaster Recovery
Thu, 14 Oct 2021 14:52:42 -0000
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Rigid and complex disaster recovery (DR) can be a thing of the past with Dell EMC Integrated System for Microsoft Azure Stack HCI.
When data Is currency, DR is non-negotiable
If your organization is like many others—of any size—it relies increasingly on data to thrive. This is particularly true for businesses that are on track to modernize their infrastructure and application architectures. For those organizations, data and the workloads that process it are truly the lifeblood of the business.
When business relies on data to function, recovery-point objectives (RPOs) and recovery-time objectives (RTOs) must be as low as possible. However, legacy disaster recovery (DR) solutions are complex to design and maintain, and they might require manual intervention during a DR scenario. These solutions can also be costly, especially if you must maintain a dedicated DR site. That’s why a flexible and performant DR solution is a crucial part of infrastructure modernization.
Stretch clustering could be the answer
Today, enterprise organizations are consolidating, refreshing, and modernizing their aging virtualization platforms with hyperconverged infrastructure (HCI). HCI architectures help customers achieve a highly automated and orchestrated cloud-operations experience. The architectures are designed to deliver high levels of performance and scalability with software-defined compute, storage and networking. HCI solutions are also designed to simplify the implementation of high availability and DR for workloads running in virtual machines (VMs) and containers.
What if you could stretch a single HCI cluster across two locations as a DR solution? That would simplify and accelerate DR. Such a solution is now within reach using Microsoft Azure Stack HCI, version 20H2 or later. Azure Stack HCI includes built-in stretch clustering capabilities, which use Storage Replica for volume replication. Stretch clustering allows organizations to split a single HCI cluster across two locations, whether they be rooms, buildings, cities or regions. It provides automatic failover of Microsoft Hyper-V VMs if a site failure occurs.
In general, stretch clustering on Azure Stack HCI is an ideal DR solution for scenarios like these:
- Introducing automatic failover with orchestration for recovery of a web-based application’s front-end server tier after a disaster at a hosting location
- Distributing primary and secondary instances of an infrastructure’s core services, such as Microsoft Active Directory, across two physical locations
- Hosting applications with lower write input/output (I/O) performance characteristics
- Running file-system-based services and other business services that can tolerate being hosted on crash-consistent volumes
- Running database workloads such as Microsoft SQL Server, which often cannot sustain the loss of even a single transaction, where using application-layer recoverability solutions such as SQL Always On availability groups might be more appropriate
Putting the solution to the test
Dell Technologies engineers conducted proof-of-concept (PoC) tests to show how Dell EMC Integrated System for Azure Stack HCI with stretch clustering can handle VM and volume placement. We also wanted to observe the impact of a real running application (Dell EMC OpenManage Enterprise) during failover scenarios. Each of the four nodes (two per site) in our testing environment included two Intel® Xeon® Gold 6230R processors and 384 GB of memory, running Azure Stack HCI, version 20H2.
We tested the following scenarios and observed the outcomes listed. For full details, read the white paper, Adding Flexibility to DR Plans with Stretch Clustering for Azure Stack HCI.
- Unplanned cluster-node failure: All VMs fully restarted on the second node at the same site in about 5 minutes.
- Unplanned site failure: Affected VMs moved and came fully back online in 15–20 minutes.
- Planned site failover: The OpenManage Enterprise application was reachable from the client device within 3 minutes of the live migration to site 2.
- Lifecycle management: Applying the BIOS, firmware and driver updates to the stretched cluster took approximately three hours, and the process had no impact on the Dell EMC OpenManage Enterprise (OME) application.
An accelerated path to simple DR
Dell Technologies offers a broad portfolio of solution configurations designed to meet the requirements of any workload. The solution for DR built on Dell EMC Integrated System for Azure Stack HCI features intelligently designed AX nodes from Dell Technologies configurations. Dell engineers validate every component of these configurations, including firmware and driver versions. Additionally, Dell ProSupport technicians know the entire solution, from hardware to operating system to Microsoft Storage Spaces Direct to networking. They can help keep the cluster operating at peak performance and availability.
To see the full details of our tests and to learn more about the stretch clustering capability in Azure Stack HCI, read the white paper, Adding Flexibility to DR Plans with Stretch Clustering for Azure Stack HCI.