The abstract of the EGEE08 conference.

General description

We propose a solution that allows windows desktop computers to run 24/24h EGEE worker nodes in a virtual machine. The proposed solution has two major parts, i) an automatic (overnight) installation system that can do the weekly automatic updates (software package management and security updates) of the windows operating system from an up to date central machine, ii) a configuration of the windows system that allows the run of the worker node on a virtual machine without well protected from the windows users.

Added value, potential user community

The main advantage of our solution is to allow the incorporation of desktop computers running Windows operating system into the EGEE grid. These computers run a VirtualBox virtual machine as a service, well separated from the users. This EGEE worker node running  with low priority apart from memory consumption  does not disturb the desktop work but uses the CPU when the host is idle. The worker node uses Virtual Private Network to connect to the grid for security reasons.

This feature is extended by an automatic torrent based windows update system that updates all windows images from the maintained central computer which generally required only once per week. The bittorrent protocol enables the fast distribution of the updated windows images which minimizes the downtime of the computer during the weekly windows updates. It is possible to freeze the virtual machine for the estimated 10 minutes of the windows update.  Unfortunately, this time is too long for open connections to survive. But jobs without internet connections survive this process.

Impact, how grid is enhanced

The main impact of this extension is the possibility to extend the capacity of the grid to computers which need to run windows during daytime for administrative or educational purposes, while keeping worker nodes available 24/24h. Running the worker node as a virtual machine has many advantages over other solutions: i) a well configured system has almost unmeasurable CPU overhead in the virtual machine, ii) the system installation of the virtual worker nodes can be the same as normal ones thus no extra work is needed, iii) it is possible to configure the windows desktops such that users cannot turn them off allowing the virtual machine to run uninterruptedly and ensure the 24/24h availability of the worker node (except for weekly updates when reboot is needed). The supplied maintenance and update solution helps system administrators to adapt this solution easily, since existing windows configurations can be used without major modifications. This solution makes it possible to easily deploy a cluster or other gLite components in a Windows based environment like a training event or university laboratory.