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Add-on services#

The following sections detail Rackspace's Microsoft Hyper-V disaster recovery (DR) and failover add-ons.

Hyper-V Replica#

Hyper-V Replica is an asynchronous VM replication technology designed for business continuity and disaster recovery. A VM can be replicated from one location to another with configurations made inside Hyper-V.

The primary server hosts the active VM that provides production workloads. The secondary (Replica) server holds a copy of the VM in an OFF state after receiving an initial copy and then delta changes from the primary VM.

VMs can be failed over to the replica location, and then reverse replicated so that the primary and secondary server are swapped.

There are two methods for configuring Hyper-V Replica:

  1. Kerberos (HTTP): Used for same domain replication.
  2. Certificate-based authentication (HTTPS): All other replication requirements.

Important

Replication using Hyper-V Replica does not work for VMs with a Shared VHDX or vFC.

Hyper-V Replica creates a copy of a live virtual machine to a replica offline virtual machine. Hyper-V Replica supports three types of Failover:

  • Test failover
  • Planned failover
  • Unplanned failover

The following table describes the characteristics of the three types of failover. Rackspace recommends that any DR is thoroughly and regularly tested end-to-end to ensure that all of the parts and pieces work as intended to provide the customer business continuity according to their specific Recovery Point Objective (RPO) and Recovery Time Objective (RTO) timelines.

  Test failover Planned failover Unplanned failover
Operation initiated on Replica VM Initiated on the primary VM and completed on the replica VM Replica VM
Is a duplicate VM created during the operation? Yes No No
How long is the operation run? Short Depends on maintenance window or regulation requirement Depends on when the primary is brought back up
Recommended frequency Short Depends on maintenance window or regulation requirement Depends on when the primary is brought back up
Recommended frequency Once a month Once in 6 months Hopefully never
What happens to the replication of the primary VM during the duration of this operation? Continues Continues. In this operation, a role-reversal happens, the primary VM becomes the replica VM and replication continues back to the primary site (that initiated the operation). Stops
Is there data loss? None None Possible
Is there downtime? None Planned downtime Unplanned downtime
Use when you want to
  • Run minimal tests to validate if your replication is on track.
  • Train your personnel on what to do in case of a disaster.
  • Test the recovery plan that you have built to test your preparation when disaster does strike.
  • Perform host maintenance on your primary and you want to run from the replica site.
  • Your primary site is expecting some power outage and you want to move over to the replica site.
  • There’s an impending natural disaster and you want to proactively act to ensure business continuity.
  • Your compliance requirements mandate that every quarter, you run your workloads from the replica site for a week.
  • Your primary site is experiencing unexpected power outage or a natural disaster.
  • Your primary site or VM has had a virus attack and you want to restore your business quickly with minimal data loss by restoring your replica VM.

Hyper-V Extended Replication#

Windows Server 2012 R2 onwards includes a Hyper-V Extended Replication feature where customers can have multiple copies of data to protect them from different outage scenarios. This means that you can extend your replica copy to a third site by using extended replication.

This functionality provides an added layer of protection to recover from your disaster. For example, you can failover your data from Site A to Site B in the primary data center and extend the replication for the protected VMs from Site B to Site C in the secondary data center.

Note

Keep in mind that utilizing Hyper-V Extended Replication has an impact on your pre-existing RPO between Site A and Site C.

Extended replication makes Hyper-V Replica more robust for disaster recovery because if an outage occurs you can recover from both the primary and extended replica. You can failover to the extended replica if your primary and secondary locations go down. The extended replica does not support application-consistent replication and must use the same VHDs that the secondary replica is using.

Requesting a failover#

To request a failover of virtual machines for Microsoft Hyper-V, you must submit a ticket to your Rackspace Microsoft Hyper-V Support team. This process is the same for managed and unmanaged virtual machines.

Cloud Replication for Hyper-V#

Rackspace's cloud replication for Hyper-V is a service that replicates VMs to the Azure cloud, but does not provide the additional failback capability that traditional disaster recovery provides. You can use Azure Site Recovery (ASR) to manage and orchestrate replication, failover, and failback of on-premise machines and Azure VMs.

The following diagram illustrates how ASR uses the cloud to support your disaster recovery:

Cloud replication for Hyper-V

For more information, see Set up disaster recovery of on-premises Hyper-V VMs to Azure.

Requesting a failover#

To request a failover of virtual machines for Microsoft Hyper-V, you must submit a ticket to your Rackspace Microsoft Hyper-V Support team. This process is the same for managed and unmanaged virtual machines.