Management of high availability services using virtualization

This thesis examines the use of virtualization in management of high availability services using open source tools. The services are hosted in virtual machines, which can be seamlessly migrated between the physical nodes in the cluster automatically by high availability software. Currently there are no complete open source solutions that provide migration of virtual machines as a method for repair. The work is based on the high availability software Heartbeat. In this work, an add-on to Heartbeat is developed, allowing Heartbeat to be able to seamlessly migrate the virtual machines between the physical nodes, when shut down gracefully. This add-on is tested in a proof of concept cluster, where Heartbeat runs Xen virtual machines with high availability. The impact of migration has been measured for both TCP and UDP services, both numerically and heuristically. The outages caused by graceful failures (e.g. rebooting) are measured to be around 1/4 seconds. Practical tests are also performed. The impression is that the outages are not noticed by the users of latency critical services as game servers or streaming audio servers.Master i nettverks- og systemadministrasjo

Comparison of organic and conventional food and food production. Part II: Animal health and welfare in Norway

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Energy Consumption of a Hybrid Additive-Subractive Manufacturing Process

Manufacturing account for a significant portion in the global electricity use and CO2emissions, and it has become essential to mitigate the environmental impact with more efficient manufacturing and resource utilisation (United Nations Environment Program (UNEP), 2011). AdditiveManufacturing (AM) has proven to be a promising manufacturing process regarding environmental and economic aspects, where one of the key environmental benefits of AM has been accounted to material savings. Recently, a new class of manufacturing processes called Hybrid Manufacturing (HM) have emerged, where AM and traditional machining are combined in one machine tool, exploiting the strengths of additive and subtractive manufacturing. As the energy requirements in HM is seldom explored in existing literature, the work of this Master's thesis aims towards developing an energy assessment framework for the HM system. This was achieved by identifying the underlying subsystems as energy consuming units. A system engineering methodology was employed for the design and analysis of the framework. To validate the proposed framework, a case study was designed to investigate the environmental footprint of multiple components made of a Titanium alloy using different processing routes.The outcome of the case study identified the energy consuming units within an HM machine and provided a baseline for a life cycle-based environmental comparison of different manufacturing approaches. The results suggested that the energy consumption in HM is stable, where the auxiliary systems account for the dominant part of the energy consumption and that process parameters not influencing the process time is relatively insignificant. The comparative study showed that AM and HM processes are more environmental friendly for components with small solid-to-cavity ratio. For larger ratios, machining proved to be more efficient

Management of high availability services using virtualization

This thesis examines the use of virtualization in management of high availability services using open source tools. The services are hosted in virtual machines, which can be seamlessly migrated between the physical nodes in the cluster automatically by high availability software. Currently there are no complete open source solutions that provide migration of virtual machines as a method for repair. The work is based on the high availability software Heartbeat. In this work, an add-on to Heartbeat is developed, allowing Heartbeat to be able to seamlessly migrate the virtual machines between the physical nodes, when shut down gracefully. This add-on is tested in a proof of concept cluster, where Heartbeat runs Xen virtual machines with high availability. The impact of migration has been measured for both TCP and UDP services, both numerically and heuristically. The outages caused by graceful failures (e.g. rebooting) are measured to be around 1/4 seconds. Practical tests are also performed. The impression is that the outages are not noticed by the users of latency critical services as game servers or streaming audio servers

Comparison of organic and conventional food and food production. Part II: Animal health and welfare in Norway

publishedVersio

Comments on: The opinion of the Agence française de sécurité sanitaire (Afssa) on changes to the control measures for sheep and goat herds in which a case of classical or atypical scrapie has been detected. Opinion of the Panel on Biological Hazards & Panel on Animal Health and Animal Welfare of the Norwegian Scientific Committee for Food Safety

The Agence française de sécurité sanitaire (Afssa) was asked by the Direction général de l’alimentation (DGAI) to comment on various proposals made by the CES ESST (expert committee on TSEs) in the EC TSE Roadmap. On January 24rd 2007, the Norwegian Scientific Committee for Food Safety (Panel on Biological Hazards and Panel on Animal Health and Animal welfare) received a request from the Norwegian Food Safety Authority for comments on Afssa’s opinion. In response, an ad hoc Working Group of experts was appointed with the mandate to draft a note regarding this issue

Comments on: The opinion of the Agence française de sécurité sanitaire (Afssa) on changes to the control measures for sheep and goat herds in which a case of classical or atypical scrapie has been detected. Opinion of the Panel on Biological Hazards & Panel on Animal Health and Animal Welfare of the Norwegian Scientific Committee for Food Safety

publishedVersio

Comments on: The opinion of the Agence française de sécurité sanitaire (Afssa) on changes to the control measures for sheep and goat herds in which a case of classical or atypical scrapie has been detected. Opinion of the Panel on Biological Hazards & Panel on Animal Health and Animal Welfare of the Norwegian Scientific Committee for Food Safety

The Agence française de sécurité sanitaire (Afssa) was asked by the Direction général de l’alimentation (DGAI) to comment on various proposals made by the CES ESST (expert committee on TSEs) in the EC TSE Roadmap. On January 24rd 2007, the Norwegian Scientific Committee for Food Safety (Panel on Biological Hazards and Panel on Animal Health and Animal welfare) received a request from the Norwegian Food Safety Authority for comments on Afssa’s opinion. In response, an ad hoc Working Group of experts was appointed with the mandate to draft a note regarding this issue