Slovak University of Technology in Bratislava Institute of Information Engineering, Automation, and Mathematics PROCEEDINGS 17th International Conference on Process Control 2009 Hotel Baník, Štrbské Pleso, Slovakia, June 9 – 12, 2009 ISBN 978-80-227-3081-5 http://www.kirp.chtf.stuba.sk/pc09 Editors: M. Fikar and M. Kvasnica Vojtešek,ˇ J., Matuš˚u,R., Bližnák,ˇ M.: The Use of Virtualization in the IT Courses, Editors: Fikar, M., Kvasnica, M., In Proceedings of the 17th International Conference on Process Control ’09, Štrbské Pleso, Slovakia, 498–505, 2009. Full paper online: http://www.kirp.chtf.stuba.sk/pc09/data/abstracts/045.html 17th International Conference on Process Control 2009 June 9–12, 2009, Strbskˇ e´ Pleso, Slovakia Po-Th-6, 045.pdf THE USE OF VIRTUALIZATION IN THE IT COURSES J. Vojtěšek*, R. Matušů*, M. Bližňák* * Faculty of Applied Informatics, Tomas Bata University in Zlín Nad Stráněmi 4511, 760 05 Zlín, Czech Republic fax : +420 57 603 5279 and e-mail : [email protected] Abstract: This article presents virtualization as one of the effective teaching and training tool in the university courses connected to IT problems. However, applications of the virtualization can be found in many other areas, not only in IT. The case study is based on the idea of virtualization of the physical computer for lower costs and security reasons. The VMware products are used nowadays at our university and the article wants to show other, especially free, alternatives to this commercial product like VirtualBox, Microsoft Virtual PC, XEN etc. Presented results provide conclusions focused mainly on the performance of the virtual computers. Keywords: Virtualization, Operating systems, Vmware, VirtualBox, XEN. 1 INTRODUCTION Hypervisor could be understand as a virtualization platform which runs different operating systems in Virtualization has big boom nowadays because of the same time on one host operating system (OS). On several benefits which are discussed below. But the other hand, paravirtualization is special virtualization technique is not a new thing; the virtualization technique, which recompiles host OS beginning of this tool in computer science can be prior to the installation inside the virtual machine. found in 1960s when IBM researches in Cambridge This article doesn’t deal with technological Scientific Center working closely with researches in background of various virtualization technologies Lincoln Laboratory introduce operating system CP- from the hardware point of view, but is aimed to their 40 which was used for virtualization on IBM software implementation and usage area mainly in the mainframe computers S/360. teaching environment. But briefly, what the virtualization is? Virtualization, So, let’s focus on the advantages which the in general, is an abstraction layer that decouples the virtualization brings to the informatics (especially in physical hardware from the operating system to the academic environment) area. This article deliver greater IT resource utilization and flexibility. describes virtual HW/SW environment used as the Virtualization allows multiple virtual machines (VM), support of parallel applications development training with heterogeneous operating systems to run in (Bližňák, 2007) and a teaching tool for teaching of a isolation, side-by-side on the same physical machine. operating systems basics. Each virtual machine has its own set of virtual hardware (e.g., RAM, CPU, NIC, etc.) upon which an operating system and applications are loaded. The operating system sees a consistent, normalized set of 2 USE OF VIRTUALIZATION hardware regardless of the actual physical hardware components. Virtualization has many fields to be applied in. Starting with simple demonstrative examples, There are many ways how to provide the virtualized advertisements, etc. through the training applications environment. An emulation of the underlying raw for teaching purposes for several not only computer- hardware can be used (so called Type 1 a 2 oriented courses in universities to the complex virtual hypervisors) as well as some form of machines in industry, training kits for NASA etc. paravirtualization. 498 17th International Conference on Process Control 2009 June 9–12, 2009, Strbskˇ e´ Pleso, Slovakia Po-Th-6, 045.pdf The main advantage of the virtualization in general is The solution of the situation described above is to that it could rapidly reduce cost and dangerousness of usage of one multi-core computer with high number the experiments. of CPUs/cores and sufficient amount of the RAM and other HW resources. This system can be then Virtualization could be generally used for simulation partitioned into several virtual parallel machines of the other OS, totally different from the host OS sharing the underlying hardware running on the host without deleting host OS, or adding a new OS to machine. To achieve this, some form of hypervisor another partition or new physical hard drive. This is monitor must run on the host machine (the currently big advantage for people who are worried about available hypervisor monitors differs mainly in the installing new OS without competent skills. Most of way how they manage the virtualized HW and the software for virtualization runs as a window with whether they run on the top of the host OS or on the virtual OS inside the host OS. There is no need to “bare metal”). reboot computer to get another OS. The first one is shown on the Figure 1. In this Another big field of usage is for the companies which scenario, the hypervisor monitor runs directly on the host Internet services. They can have one server with hardware which is partitioned into several numbers of co called dedicated servers for rent. independent virtual machines where each of those is There is no need to have numbers of physical servers configured as two-processor computer with adequate which reduces cost rapidly too. Another benefit could amount of assigned physical system memory. be found in the easily portability of the VM to another – just copy the image file of the virtual machine which is usually one big file with a few small configuration files to the new hard disk and VM could run again. Security is another advantage of the solution. Bug, viruses and worms testing uses virtualization as important tool too. Security is very important aspect of development and the risk of computer virus infection can be reduced with the use of VM for testing. This paper will present the use of virtualization from another point of view – as a teaching tool in two courses in Tomas Bata University in Zlin – Parallel Programming and Operating Systems. Fig. 1 Virtualized environment without host OS 2.1 The Use in the Parallel Programming Course The second possible configuration shown in the The study course Parallel Programming is mandatory Figure 2 differs from the first one in the sense that the subject for all students in the summer term of the first hypervisor monitor doesn't run directly on the year in master-degree studies of the Information virtualized hardware, but on the top of any supported technologies study branch, study program called OS. This scenario is suitable for a situation when the Engineering informatics. underlying hardware is not directly supported by the hypervisor so some other suitable OS must be used Imagine a situation when students are learning for managing it and the hypervisor uses the various programming techniques dealing with virtualized HW via the host OS’s device drivers. algorithm parallelization and distributed computing. One of the most important parts of the learning curve is the verification of the obtained knowledge in the real conditions, so it is obvious that students should test their parallel application on the real parallel computation system. Assume that the students are learning the programming techniques suitable for SMP parallel computers with the shared memory architecture (generally all presently shipped multi- core desktop computers, workstations, servers and notebooks). One of the possible ways how to do this is to provide each student with one multi-core computer. It is obvious that this solution is not ideal – the multi-core computer are still quite expensive, moreover, the utilization of their computing power and other hardware resources (RAM, disk space, etc.) can be poor in this scenario. So, what solution provides efficient learning conditions as well as the Fig. 2 Virtualized environment with host OS most effective hardware and software utilization? 499 17th International Conference on Process Control 2009 June 9–12, 2009, Strbskˇ e´ Pleso, Slovakia Po-Th-6, 045.pdf 2.2 The Use in Operating Systems Course In the first one, so called emulation, is hardware fully virtualized by the software. Advantages can be found In common offices the number of people accessing in absolutely separated virtualized OS from the host one desktop PC, workstation or notebook is limited. OS, it can run applications which does not have In contrast, in academic environment, especially in supported hardware available and host OS cannot be the case of computer used by the students the amount modified. Disadvantage of this method is that it is of the users is simply great. Moreover, often is very very slow and very system-demanding. Typical difficult (sometimes impossible) to watch all members of this group are simulators of old students’ activities performed on the workstations. It computers (ZX Spectrum, Atari etc.), operating is obvious that this fact can quite often lead to systems (DOSBox, DOSEMU etc.) and special tools corruption of PC’s operation system integrity and like Bochs, QEMU etc. necessity to reinstall whole OS all software equipment. This is much more critical in the The second group of software is focused on the Operating Systems course, where we expect students virtualization on the operating system level. This to modify system configuration which could corrupt solution has much better performance results with system and lead to reinstall of the system.