4.3 Cloud Burst From Data Center to Cloud

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4.3      Cloud BurstFrom Data Center to Cloud

Actors: cloud-subscriber, cloud-provider, cloud-management-broker

Goals: Maintain required service levels for an agency's data-center hosted process, by dynamically allocating/deallocating cloud computer or storage resources to service current demands.

Assumptions: Assumes the Use case "Open an Account"

Success Scenario 1 (base, IaaS): 

Cloud-subscriber provisions and maintains cloud-provider-1 virtual machine images and/or configured storage capacity designed to support cloud-subscriber-defined units of work ranging in scope from individual computing or storage tasks to entire distributed applications.

        Cloud-subscriber establishes load monitoring processes for the units of work concerned, and load threshold and sensitivity limits for cloud bursting.  Upper limits govern starting new processes on cloud-provider to handle increasing load; lower limits govern stopping cloud-provider processes to handle decreasing load.

        As monitored load triggers threshold limits, processes start or stop on cloud-provider-1 infrastructure to maintain required service levels.

Failure Conditions 1 (base): Failed allocation or deallocation event

Failure Handling 1 (base): Failed allocation or deallocation event: Cloud-provider-1 notifies cloud-subscriber.  Cloud-subscriber either communicates with cloud-provider-1 for resolution within an acceptable SLA or has access to automated cloud-provider-1 notification and resolution.  Failed deallocation events can result in excess agency charges and must be covered in SLA agreements.

Success Scenario 2 (Manual Bursting, IaaS): Cloud-subscriber manually allocates and deallocates cloud-provider resources based on threshold notifications.

Failure Conditions 2 (Manual Bursting): N/A

Failure Handling 2 (Manual Bursting): N/A

Success Scenario 3 (Automated Bursting, IaaS): Cloud-management-broker processes monitor load and threshold limits and allocate or deallocate cloud-provider-1 resources using programming interfaces provided by cloud-provider.

Failure Conditions 3 (Automated Bursting): Failed event detection

Failure Handling 3 (Automated Bursting): Cloud-management-broker independently monitors its event detection services and notifies cloud-subscriber of outages so cloud-subscriber can fall back to manual bursting scenarios.

Credit: N/A