Abstract

Cloud is becoming one of the most popular means of delivering computational services to users who demand services with higher availability. Virtualization is one of the key enablers of the cloud infrastructure. Availability of the virtual machines along with the availability of the hosted software components are the fundamental ingredients for achieving highly available services in the cloud. There are some availability solutions developed by virtualization vendors like VMware HA and VMware FT. At the same time the SAForum specifications and OpenSAF as a compliant implementation offer a standard based open solution for service high availability. Our work aims at comparing virtualization solutions, VMware, with OpenSAF from the high availability perspective, and proposes appropriate combinations to take advantage of the strengths of both solutions. To conduct our evaluations, we established metrics, selected a video streaming application and conducted experiments on different architectures covering OpenSAF in physical and virtual machines, the VMware HA and VMware FT. Based on the analysis of the initial measurements, we proposed other architectures that combine OpenSAF high availability and the virtualization provided by VMware. Our proposal included architectures targeting two types of hypervisors, non-bare-metal and bare-metal. In both of these proposed architectures we used OpenSAF to manage the availability of the VM and the case study application running in the VM. The management of the availability of the VM is slightly different in these architectures because of the types of the hypervisors. In these architectures we used the libraries and the mechanisms which are available in many other hypervisors. Our work compared to other works on high availability in virtual environments has the important advantage of covering the application/service failure.