A multi-site virtual cluster system for wide area networks
Takahiro Hirofuchi, Takeshi Yokoi, Tadashi Ebara, Yusuke Tanimura, Hirotaka Ogawa, Hidetomo Nakada, Yoshio Tanaka, Satoshi Sekiguchi · 2008
A virtual cluster is a promising technology for reduc-ing management costs and improving capacity utiliza-tion in datacenters and computer centers. However, re-cent cluster virtualization systems do not have the max-imum scalability and flexibility required, due to lim-ited hardware resources at one site. Therefore, we are now developing an advanced cluster management sys-tem for multi-site virtual clusters; which provides a vir-tual cluster composed of distributed computer resources over wide area networks. This system has great advan-tages over other cluster management systems designed only for single-site resources; users can create a clus-ter of virtual machines from local and remote physical clusters in a scalable manner, and dynamically change the number of cluster nodes on demand, seamlessly. In our system, a multi-site cluster achieves a monolithic system view of cluster nodes to enable existing appli-cations to be deployed quickly and managed flexibly, just as in physical clusters. In this paper, we propose an advanced cluster virtualization mechanism composed of two key techniques. An L2 network extension of virtual machine networks allows transparent deployment over networks for distributed virtual cluster nodes, and a transparent package caching mechanism greatly opti-mizes data transfers in virtual cluster deployment over network latencies. Experimental results show multi-site virtual clusters have sufficient feasibility in WAN envi-ronments and promise great scalability for a large-scale number of virtual nodes. 1