Availability analysis for deployment of in-cloud applications

Abstract

Deploying critical applications in the cloud introduces uncertainties for availability that have traditionally been under the direct control of the application owner. The cloud infrastructure impact to availability is due to dynamic resource sharing as well as limited visibility/control of the underlying infrastructure and its quality of service. It is important to assess the availability of the critical application considering the weak availability guarantees provided by the cloud infrastructures under a broad range of scenarios, including rare scenarios like infrastructure failures and disasters. In this paper, we propose a deployment architecture-driven availability analysis model that considers uncertain rare events explicitly and bridges the gap of weak infrastructure availability and critical application availability. The models require initial calibration and validation, which is achieved by using data from commercial products and industry best practices. We use the proposed models to reevaluate the industry best practice under rare infrastructure events.