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arXiv · 1205.0483

High availability using virtualization - 3RC

Federico Calzolari·Silvia Arezzini·Alberto Ciampa·Enrico Mazzoni·Andrea Domenici·Gigliola Vaglini
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Abstract

High availability has always been one of the main problems for a data center. Till now high availability was achieved by host per host redundancy, a highly expensive method in terms of hardware and human costs. A new approach to the problem can be offered by virtualization. Using virtualization, it is possible to achieve a redundancy system for all the services running on a data center. This new approach to high availability allows the running virtual machines to be distributed over a small number of servers, by exploiting the features of the virtualization layer: start, stop and move virtual machines between physical hosts. The 3RC system is based on a finite state machine, providing the possibility to restart each virtual machine over any physical host, or reinstall it from scratch. A complete infrastructure has been developed to install operating system and middleware in a few minutes. To virtualize the main servers of a data center, a new procedure has been developed to migrate physical to virtual hosts. The whole Grid data center SNS-PISA is running at the moment in virtual environment under the high availability system.

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Federico Calzolari, Silvia Arezzini, Alberto Ciampa, Enrico Mazzoni, Andrea Domenici, Gigliola Vaglini. 2012-05-02. High availability using virtualization - 3RC. https://doi.org/10.1088/1742-6596%2F219%2F5%2F052017

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