Towards an Evaluation Framework for Availability Solutions in the Cloud Proceedings of ISSRE 2014 Proceedings of ISSRE 2014 Majid Hormati, Ferhat Khendek Maria Toeroe Concordia UniversityEricsson,

Motivation  Different factors impact the availability of applications in the Cloud  the availability of VMs,  Cloud infrastructure,  networking, etc.  Users need a unified approach to compare and evaluate the different availability solutions 2

Evaluation Criteria 3  For Service Providers:  E.g. application components, VM, physical host  Fault detection and reporting  Whether the failures of service provider entities are detected  Repair actions  Whether the faulty entity is repaired e.g. restarted  For Services:  E.g. application’s service, VM as a service  Recovery of the service  Whether the service provided by the failing service provider entity is recovered  Support for service continuity  Whether the service can continue from the point of failure or it restarted

Evaluation Framework 4  Evaluation Parameters

Evaluating Existing/Potential Solutions 5 1: Application is started with the VM 2: The reaction is at VM level Recovery and repair combined into a single action

Some Other Aspects 6  Redundancy models  OpenSAF: No-redundancy, 2N, N+M, NWay, NWay-Active  Pacemaker: 2Way-Active (Active/Active), 2N (Active/Passive), N+M, NWay-Active (N-to-N)  Heat: No-Redundancy  VMWare HA: No-Redundancy  WMWare FT: 2N  Deployment complexity  Compared to Heat we found OpenSAF and Pacemaker easier to deploy – they are more mature  …