Tag Archives: Virtualization

Adoption of Virtualization Technologies in Production Grids

Last Tuesday I gave a talk about on-demand resource provision in the 7th NRENs and Grids Workshop organized by Terena at Trinity College Dublin. One of the more interesting presentations was given by Stephen Childs (Trinity College Dublin & Grid-Ireland), Deploying Virtualization in a Production Grid. In his talk, Stephen describes the results of a survey about the use of virtualization technologies in production grids (EGEE, OSG, TeraGrid, NorduGrid…). Let me summarize the main conclusions:

  • Large uptake of virtualization (71% of sites)
  • Xen is the most used technology
  • Site and central services (front-end, information…), and not worker nodes, are the most common virtualized
  • Performance and management concerns are the main barriers for adoption of virtualization

Steve also defines a adoption roadmap of virtualization technologies in Grid sites consisting of three stages:

  • Manual installation of VMs
  • Integration of VMs with standard configuration tools
  • Tools to support on-demand provision of VMs, such as OpenNebula 
We are now entering the third stage, with a growing number of sites evaluation the advantages of using a virtual infrastructure for all the services, including worker nodes. 
Finally I would like to highlight the work being done in Grid-Ireland with the application of virtualization technologies in order to create virtual gateways, a full gLite grid site in one box.

The OpenNebula Engine for Data Center Virtualization and Cloud Solutions

Virtualization has opened up avenues for new resource management techniques within the data center. Probably, the most important characteristic is its ability to dynamically shape a given hardware infrastructure to support different services with varying workloads. Therefore, effectively decoupling the management of the service (for example a web server or a computing cluster) from the management of the infrastructure (e.g. the resources allocated to each service or the interconnection network).

A key component in this scenario is the virtual machine manager. A VM manager is responsible for the efficient management of the virtual infrastructure as a whole, by providing basic functionality for the deployment, control and monitoring of VMs on a distributed pool of resources. Usually, these VM managers also offer high availability capabilities and scheduling policies for VM placement and physical resource selection. Taking advantage of the underlying virtualization technologies and according to a set of predefined policies, the VM manager is able to adapt the physical infrastructure to the services it supports and their current load. This adaptation usually involves the deployment of new VMs or the migration of running VMs to optimize their placement.

The dsa-research group at the Universidad Complutense de Madrid has released under the terms of the Apache License, Version 2.0, the first stable version of the OpenNebula Virtual Infrastructure Engine. OpenNebula enables the dynamic allocation of virtual machines on a pool of physical resources, so extending the benefits of existing virtualization platforms from a single physical resource to a pool of resources, decoupling the server not only from the physical infrastructure but also from the physical location. OpenNebula is a component being enhanced within the context of the RESERVOIR European Project.

The new VM manger differentiates from existing VM managers in its highly modular and open architecture designed to meet the requirements of cluster administrators. OpenNebula 1.0 supports Xen and KVM virtualization platforms to provide several features and capabilities for VM dynamic management, such as centralized management, efficient resource management, powerful API and CLI interfaces for monitoring and controlling VMs and physical resources, fault tolerant design… Two of the outstanding new features are its support for advance reservation leases and on-demand access to remote cloud provider

Support for Advance Reservation Leases

Haizea is an open source lease management architecture that OpenNebula can use as a scheduling backend. Haizea uses leases as a fundamental resource provisioning abstraction, and implements those leases as virtual machines, taking into account the overhead of using virtual machines (e.g., deploying a disk image for a VM) when scheduling leases. Using OpenNebula with Haizea allows resource providers to lease their resources, using potentially complex lease terms, instead of only allowing users to request VMs that must start immediately.

Support to Access on-Demand to Amazon EC2 resources

Recently, virtualization has also brought about a new utility computing model, called cloud computing, for the on-demand provision of virtualized resources as a service. The Amazon Elastic Compute Cloudi s probably the best example of this new paradigm for the elastic capacity providing. Thanks to virtualization, the clouds can be used efficiently to supplement local capacity with outsourced resources. The joint use of these two technologies, VM managers and clouds, will change arguably the structure and economics of current data centers. OpenNebula provides support to access Amazon EC2 resources to supplement local resources with cloud resources to satisfy peak or fluctuating demands.

Scale-out of Computing Clusters with OpenNebula and Amazon EC2

As use case to illustrate the new capabilities provided by OpenNebula, the release includes documentation about the application of this new paradigm (i.e. the combination of VM managers and cloud computing) to a computing cluster, a typical data center service. The use of a new virtualization layer between the computing cluster and the physical infrastructure extends the classical benefits of VMs to the computing cluster, so providing cluster consolidation, cluster partitioning and support for heterogeneous workloads. Moreover, the integration of the cloud in this layer allows the cluster to grow on-demand with additional computational resources to satisfy peak demands.

Ignacio Martín Llorente

First Technology Preview of the Haizea Lease Manager

I would like to give a warm welcome to Haizea to the virtualization ecosystem. The new technological component is an open-source VM-based lease management architecture, which can be used

  • As a platform for experimenting with scheduling algorithms that depend on VM deployment or on the leasing abstraction.
  • In combination with the OpenNebula virtual infrastructure manager, to manage a Xen or KVM cluster, allowing you to deploy different types of leases that are instantiated as virtual machines (VMs).

Its full integration with OpenNebula will be part of the next Technoloy Preview (TP1.1), due mid-july. Haizea is being developed by Borja Sotomayor, a PhD student at the University of Chicago, who is now visiting our research group partially funded by the European Union’s FP7 Reservoir project (“Resources and Services Virtualization without Barriers”).

Ignacio Martín Llorente

HPC, Grid and Cloud Computing in Cetraro

I am attending the INTERNATIONAL ADVANCED RESEARCH WORKSHOP ON HIGH PERFORMANCE COMPUTING AND GRIDS in Cetraro (Italy). This is the 9th edition of the workshop organized by Prof. Lucio Grandinetti. I have to say the venue of the workshop, at Grand Hotel San Michele, is just perfect. The panel of speakers includes representatives of the more relevant Grid and HPC research initiatives and technologies around the world. The abstracts of the presentations are available online at the workshop site.

Cloud Computing for on-Demand Resource Provisioning

This is the title of the talk that I gave in the Workshop. The aim of the presentation was to show the benefits of the separation of resource provisioning from job execution management in different deployment scenarios. Within an organization, the incorporation of a new virtualization layer under existing Cluster and HPC middleware stacks decouples the execution of the computing services from the physical infrastructure. The dynamic execution of working nodes, on virtual resources supported by virtual machine managers such as the OpenNEbula Virtual Infrastructure Engine, provides multiple benefits, such as cluster consolidation, cluster partitioning and heterogeneous workload execution. When the computing platform is part of a Grid Infrastructure, this approach additionally provides generic execution support, allowing Grid sites to dynamically adapt to changing VO demands, so overcoming many of the obstacles for Grid adoption.

The previous scenario can be modified so the computing services are executed on a remote virtual infrastructure. This is the resource provision paradigm implemented by some commercial and scientific infrastructure Cloud Computing solutions, such as Globus VWS or Amazon EC2, which provide remote interfaces for control and monitoring of virtual resources. In this way a computing platform could scale out using resources provided on-demand by a provider, so supplementing local physical computing services to satisfy peak or unusual demands. Cloud interfaces can also provide support for the federation of virtualization infrastructures, so allowing virtual machine managers to access resources from remote resources providers or Cloud systems in order to meet fluctuating demands. The OpenNEbula Virtual Infrastructure Engine is being enhanced to access on-demand resources from EC2 and Globus-based clouds. This scenario is being studied in the context of the RESERVOIR– Resources and Services Virtualization without Barriers — EU-funded initiative

Download the slides

Towards a New Model for the Infrastructure Grid

This is the title of my contribution in the Panel “From Grids to Cloud Services”, chaired by Charlie Catlett, in the Workshop. The aim of the presentation was to introduce the discussion on the future of compute grid infrastructures, from infrastructures for the sharing of basic resource services to infrastructures for the sharing of hardware resources. A widely distributed virtual infrastructure, inspired in the federation of cloud systems as providers of virtualized resources (hardware) as a service, would not require end users to learn new interfaces and port their applications to the expected runtime environment. The sharing of resources would be performed at resource level, so local job managers could scale out to partner or commercial clouds, transparently to end users. This new model provides additional benefits, such as the support to any service, seamless integration with any service middleware stack…; at the cost of the virtualization overhead in the execution of the jobs.

It was very interesting to share this position on cloud computing with other researchers from Grid and HPC fields. So the question is: Are the existing compute Grid Infrastructures going to evolve to Grids of Clouds?. In other words, Which model is better for end users and site administrators?, to share basic infrastructure services or the physical infrastructure?.

Download the slides

Ignacio Martín Llorente

A Virtual Infrastructure Layer for Cluster and Grid Computing

Cluster, and so Grid site, administrators have to deal with the following requirements when configuring and scaling their infrastructure:

  • Heterogeneous configuration demands. Users often require specific versions of different software components (e.g. operating system, libraries or post-processing utilities). The cost of the installation, configuration and maintenance of user-specific or VO-specific worker nodes limits the flexibility of the infrastructure.
  • Performance partitioning. Most of the computing infrastructures do not allow administrators to isolate and partition the performance of the physical resources they devote to different computing clusters or Grid infrastructures. This limits the quality of service and reliability of actual computing platforms, preventing a wide adoption of the Grid paradigm.

In order to overcome these challenges, we propose a new virtualization layer between the service and the physical infrastructure layers, which seamless integrates with existing Grid and cluster middleware stacks. The new virtualization layer extends the benefits of VMMs (Virtual Machine Monitors) from a single physical resource to a cluster of resources, decoupling a server not only from the physical infrastructure but also from the physical location. In the particular case of computing clusters, this new layer supports the dynamic execution of computing services, working nodes, from different computer clusters on a single physical cluster.


OpenNebula is the name of a new open-source technology that transforms a physical infrastructure into a virtual infrastructure by dynamically overlaying VMs over physical resources. So computing services, such as working nodes managed by existing LRMs (Local Resource Managers) like SGE, Condor, OpenPBS…, could be executed on top of the virtual infrastructure; so allowing a physical cluster to dynamically execute multiple virtual clusters.

The separation of resource provisioning, managed by OpenNebula, from job execution management, managed by existing LRMs, provides the following benefits:

  • Cluster consolidation because multiple virtual working nodes can run on a single physical resource, reducing the number of physical systems and so space, administration, power and cooling requirements. The allocation of physical resources to virtual nodes could be dynamic, depending on its computing demands, by leveraging the migration functionality provided by existing VMMs
  • Cluster partitioning because the physical resources of a cluster could be used to execute virtual working nodes bound to different virtual clusters
  • Support for heterogeneous workloads with multiple (even conflicting) software requirements, allowing the execution of software with strict requirements as jobs that will only run with a specific version of a library or legacy application execution

Consequently, this approach provides the flexibility required to allow Grid sites to execute on-demand VO-specific working nodes and to isolate and partition the physical resources. Additionally, the architecture offers other benefits to the administrator of the cluster, such as high availability, support for planned maintenance and changing capacity availability, performance partitioning, protection against malicious use of resources…

The idea of a virtual infrastructure which dynamically manages the execution of VMs on physical resources is not new. There exist several VM Management proprietary solutions to simplify the use of virtualization, so providing the enterprise with the potential benefits this technology may offer. Examples of products for the centralized management of the life-cycle of a VM workload on a pool of physical resources are: Platform VM Orchestrator, IBM Virtualization Manager, Novell ZENworks, VMware Virtual Center, and HP VMManager.

The OpenNebula Virtual Infrastructure Engine differentiates from those VM management systems in its highly modular and open architecture to meet the requirements of cluster administrators. The OpenNebula Engine provides a command line interface for monitoring and controlling VMs and physical resources quite similar to that provided by well-known LRMs. Such interface allows its integration with third-party tools, such as LRMs, service adapters, VM image managers…; to provide a complete solution for the deployment of flexible and efficient computing clusters. The service layer decoupling from the infrastructure layer allows an straightforward extension of the previous idea to any kind of service. In this way any physical infrastructure can be transformed into a very effective provisioning platform.

A Technology Preview of OpenNebula is available for download under the terms of the Apache License, version 2.0.

Ignacio Martín Llorente

dsa-research Group Leads Activity on VM Management in Main EU-funded Initiative in Cloud Computing

RESERVOIR– Resources and Services Virtualization without Barriers — is a 17-million-Euro EU-funded initiative in the first FP7 call for proposals for Objective 1.2 Software and Service Architectures, Engineering and Infrastructure. RESERVOIR is a joint research programme coordinated by IBM with 13 European partners: Elsag Datamat, CETIC, OGF.eeig standards organisation, SAP Research, Sun Microsystems, Telefonica Investigacion y Desarrollo, Thales, Umea University, University College of London, Universidad Complutense de Madrid, University of Lugano and University of Messina. The kick-off of this 3-year project was held at IBM Haifa from February 5 to February 7.

The aim of RESERVOIR is to develop the infrastructure technology to support the setup and deployment of services on-demand, at competitive costs, across administrative domains, assuring quality of service. The project will develop new Grid and virtualization technologies that will help automate the fluctuating demand for resources in a cloud-computing environment. The three main technological activities in Reservoir cover: service management, Virtual Execution Environment management and provision, and Virtual Execution Environment infrastructure enablenment.

RESERVOIR will build on the notion of Virtual Execution Environment (VEE), an abstraction of an execution environment that will allow to develop a set of high level management components that are not tied to any specific environment. The project will investigate the applicability and limitations of specific implementations of VEEs, such as Virtual Machines (VMs) and Virtual Java Service Containers (VJSCs).


The goals of Activity 3: Management of Virtual Execution Environments , led by the dsa-research group, are:

  • To enable dynamic deployment and reallocation of VEEs across physical resources.
  • To provide QoS resource reservation support.
  • To manage VEEs and their inner service tasks across administrative domains (i.e., multiple service sites or grid environments).