Orchestrating the Deployment of High Availability Services on Multi-zone and Multi-cloud Scenarios

Cloud computing has become one of the most used platforms to deploy High Availability (HA) solutions for its flexibility, on-demand provisioning, and elasticity. However, although many providers offer specific tools for HA support, like floating IPs and load balancing, the analysis of downtime at public cloud providers in previous years shows that a combination of several availability zones or cloud providers is required to achieve “five nines” availability. Besides reducing the chances of failure, the use of multiple availability zones and geographically distributed clouds may additionally bring performance and cost benefits. However, the orchestration, in an efficient and adaptive way, of HA multi-tier services in multi-zone and multi-cloud environments brings several challenges. This paper presents a novel orchestration method to automate the deployment and management of high availability multi-tier services on multiple availability zones, by introducing new affinity mechanisms, such as VM to location and role to role affinity/anti-affinity rules. Furthermore, we also extend this solution to multi-cloud scenarios, based on the replication or distribution of the service components among various clouds, along with their corresponding affinity rules.