Virtual clusters are widely used computing platforms than can be deployed in multiple cloud platforms. The ability to dynamically grow and shrink the number of nodes has paved the way for customised elastic computing both for High Performance Computing and High Throughput Computing workloads. However, elasticity is typically restricted to a single cloud site, thus hindering the ability to provision computational resources from multiple geographically distributed cloud sites. To this aim, this paper introduces an architecture of open-source components that coherently deploy a virtual elastic cluster across multiple cloud sites to perform large-scale computing. These hybrid virtual elastic clusters are automatically deployed and configured using an Infrastructure as Code (IaC) approach on a distributed hybrid testbed that spans different organizations, including on-premises and public clouds, supporting automated tunneling of communications across the cluster nodes with advanced VPN topologies. The results indicate that cluster-based computing of embarrassingly parallel jobs can benefit from hybrid virtual clusters that aggregate computing resources from multiple cloud back-ends and bring them together into a dedicated, albeit virtual network.

虚拟集群是广泛使用的计算平台，可以部署在多个云平台中。动态增加和减少节点数量的能力为高性能计算和高吞吐量计算工作负载的定制弹性计算铺平了道路。但是，弹性通常仅限于单个云站点，因此阻碍了从多个地理分布的云站点提供计算资源的能力。为此，本文介绍了一种开放源代码组件的体系结构，该组件可在多个云站点上一致地部署虚拟弹性集群以执行大规模计算。这些混合虚拟弹性集群是使用基础设施即代码（IaC）方法在分布于不同组织（包括本地和公共云）的分布式混合测试床上自动部署和配置的，从而支持使用高级VPN拓扑在集群节点之间自动建立通信隧道。结果表明，令人尴尬的并行作业的基于集群的计算可以受益于混合虚拟集群，该集群将来自多个云后端的计算资源聚合在一起，并将它们整合到一个专用的虚拟网络中。