Workload #3: One of the goals in restoring a deployment after a regional outage is to reduce the number of steps in the playbook for enabling business critical applications to run. Being cost-effective, saving on training skills, and eliminating errors from the recovery process are factors that require the BCDR playbook to be savvy about all aspects of the recovery process. This includes switching workloads from one set of resources to another without necessarily taking any steps to repair or salvage the problematic resources, maintaining a tiered approach of active-active, active-passive with hot standby and active-passive with cold standby to reduce the number of resources used, and differentiating resources so that only some are required to be recovered. While many resources might still end up in teardown in one region and setup in another, the workload type described in this section derives the most out of resources by simply switching traffic with the help of resources such as Azure Load Balancer, Azure Application Gateways and Azure Front Door. Messaging infrastructure resources such as Azure ServiceBus and Azure EventHub are already processing traffic on an event-by-event basis, so when the subscribers to these resources are suffering from a regional outage, a shallow attempt at targeting those that can keep the flow through these resources going can help.  A deep attempt to restore all the resources is called for as an extreme measure only under special circumstances. This way, there is optimum use of time and effort in the recovery.

Reference: 

1. Business Continuity and Disaster Recovery.docx

2. BCDRBestPractices.docx

3. DRTerminology.docx

4. BCDRPatterns.docx