Distributed virtual scenarios over multi-host Linux environments

Virtualization based testbeds are nowadays widely used for the creation of the network environments needed to test protocols and applications. Virtualization has highly contributed to reduce the cost of testbeds setup, either in terms of hardware resources needed or work effort. However, the complexity of present networks arises the need to create very complex testbeds, made out of tenths or even hundreds of virtual machines, interconnected according to specific topologies. The paper presents a tool for the deployment and management of virtual network scenarios over clusters of Linux servers. VNX (Virtual Networks over LinuX) tool allows the definition of virtual network scenarios (virtual machines number and characteristics, interconnection topology, etc.) and controls their deployment over either a Linux server or a cluster of servers. The tool allows the user to control how the virtual scenario is distributed over the different cluster servers, using algorithms ranging from simple round-robin to complex user-defined, as well as restriction rules (i.e. virtual machine X must run over host Y). VNX is based on two previous tools (VNUML/EDIV) which have been extensively enhanced with new functionalities such as virtual machine autoconfiguration (using OVF-like approach), support of several virtualization hypervisors through the integration of libvirt API, and the integration of router virtualization technologies.