ATOL: Virtualization
Marek Grac xgrac@f i.muni.cz
Red Hat Czech s.r.o. / Faculty of Informatics, Masaryk University
Advanced Topics of Linux Administration
Marek Grác xgrac@fi.muni.cz ATOL: Virtualization
Introduction to Virtualization
► 1960's: IBM mainframes - single user system
► Virtualization (running single-user OS several times)
► Introducing virtual memory
Main benefit is time sharing (typically in universities, research centres)
► 1998: VMWare (Berkeley/Stanford); IPO (NYSE:VMW) in 2007
► 2003: Xen (XenSource/Uni. of Cambridge); bought by Citrix in 2007
► 2005: KVM (Qumranet); bought by Red Hat in 2008
Marek Grac xgrac@fi.muni.cz ATOL: Virtualization
Characteristics
► Advantages
► Security
► Better utilization of computers (power, CPU, rack space) *■ Higher availability of services
*■ Low-cost solution
► Disadvantages
► Performance issues
*■ Virtualization on Linux is new technology *■ Very difficult to solve issues
Marek Grac xgrac@fi.muni.cz ATOL: Virtualization
Full-virtualization
► No modification are needed in guest OS
► Total abstraction of underlying physical system
► HW support: Intel VT (CPU flag vmx), AMD SVM (svm)
Marek Grac xgrac@fi.muni.cz ATOL: Virtualization
Paravirtualization
► Requires user modification of guest OS (eg. linux-image-xen)
► Provides near native performance (<5% at best)
Marek Grac xgrac@fi.muni.cz ATOL: Virtualization
Management of Virtual Machnies
libvirt, virsh
► Large deployment
► VMWare Virtual Center
► Red Hat Virtualization Manager (RHEV-M)
► Clouds
► Infrastructure as a Service (IAAS) - Amazon WS, Microsoft Azure
► Platform as a Service (PAAS) - Google App Engine, (Sales)Force.com
► Software as a Service (SAAS) - Google Apps
Marek Gräc xgrac@fi.muni.cz ATOL: Virtualization
Virtualized Resources
Virtual CPUs (vcpu)
► Virtual disks (/dev/xvda)
► Virtual network interfaces (VNIC), identification by MAC addresses
► Identification of guests using
► domain name (domain-name) - user given
► identity (domain-id) - unique, non-persistent
► UUID - persistent, assigned at first installation
Marek Grac xgrac@fi.muni.cz ATOL: Virtualization
Lab: Installation
► Goals:
► Create a virtual machine on your computer using kickstart
► Setup network connection through your 'real' machine
► Using a LVM snapshots create a new virtual machine from existing one
Marek Grac xgrac@fi.muni.cz ATOL: Virtualization
Lab: Prepare a paper
► Themes:
► Compare VMWare, Xen, KVM, .. .
► Format:
► Short presentation (15-20 minutes; 5-7 slides)
► Paper containing comparision (500 words)
Marek Grac xgrac@fi.muni.cz ATOL: Virtualization