Using Open Source Virtualization Technology In
Computer Education
By: Ronny L. Bull
Advised By: Geethapriya Thamilarasu, Ph.D.
Fall 2011


Create a scalable virtualization server cluster using Open Source technology

Used by students & faculty for labs, research,
& development

Used by CS Admins to migrate aging physical servers to virtual environment

Provide fine grained user access to virtual machines via the web using current LDAP authentication


Allows an organization to leverage the power of multi-core server hardware to host multiple virtual servers on a single physical host.

Consolidates a large server farm down to a few powerful machines which have the advantage of saving space and energy costs while still retaining the same level of service that they previously relied upon.


Makes server virtualization possible by creating a basic abstraction layer of software that sits directly on the hardware below any operating system.

Responsible for CPU scheduling and memory partitioning of the various virtual machines running on the physical hardware

Controls execution of virtual machines as they share the common processing environment and resources


Has no knowledge of networking, external storage devices, video, or any other common
I/O functions

Most enterprise virtualization solutions offer their hypervisors for free. ( Microsoft Hyper-V,
Citrix XenServer, VMWare ESXi)


The Host operating system is a privileged virtual machine that has special rights to access physical I/O resources as well as manages the other virtual machines running on the system

The Guest operation systems have no direct access to the physical hardware on the machine, and rely on the host to manage them

The Host must be online before any Guests are allowed to be started


Most enterprise virtualization solutions offer free hypervisors however the utilities to manage them can be expensive

Enter Xen, the open source hypervisor

Citrix bases all of it's products on Xen

Xen Cloud Platform (XCP) is an open source implementation of Citrix XenServer

CentOS Linux based distribution

Minimal documentation


Motherboard: SUPERMICRO MBDX9SCM-O
Server Motherboard (SandyBridge) w/ 2 integrated 1000MB Intel NIC's

Processor: Intel Xeon E3-1240 @ 3.30GHz
Quad Core w/ Hyper Threading

RAM: 16 GB Crucial DDR3 SDRAM ECC
Unbuffered Server Memory

Hard Drives: 2x Seagate Momentus XT
500GB Hybrid


Hard Drive Mounts: 2x Mushkin Enhanced drive adapter bracket

Rack Mount Case: Antec Take 4 + 4U With
650W Power Supply (Quiet Computing)

Rack Rails: Antec 20" Side Rails

Total Cost Per Server: $1,331.46


Repeatable lockups on two of the three servers when pushing heavy I/O

Performed extensive hardware diagnostic and stress tests

Swapped parts

Found both motherboards were faulty and had to be RMA'd


Installed from CDROM

Setup management interface on Admin subnet

Created local ISO storage repositories

Extended the Default LVM Volume Group to include the remaining 450GB from second hard drive


Created firewall rules for the Eth0 management interface, connected to Admin subnet



Created VLAN entries on all of the servers to support all of the VLAN's on the network
Assigned all VLANS to Eth1 – VM interface
Assigned Eth1 to 201 VLAN – Student, and gave it an IP address

Connected Eth1 to trunked port and setup firewall rules for access


Can not clone servers to produce new ones because of UUID's on resources

Each server must be setup from scratch

Can use Citrix XenCenter to manage multiple servers from a single remote location

Export, Import, Create, Connect To, & Manage
VM's

Snapshots, Resource Management, CPU
Priority, & Templates


Created three server pools



CSAdmin – For migrated CS dept. servers
NCS-Student – NCS Lab server
CS-Student – CS Lab/Research server

More servers will be added as they are retired from ITS and become available


Default Linux templates do not boot from
CDROM

30 day license issue

XenCenter snapshot issue (Version)

 https://xen1-web.cs.sunyit.edu

XVP Appliance – turnkey virtual appliance created to manage Citrix XenServer & XCP servers

LDAP integration

Fine grained user access control on a per machine or per pool basis

Web based using https

Access & Setup via command line utility


User only needs access to port 443 of xen1web appliance

All console connections to virtual machines are done over the standard VNC TCP port
5900 from xen1-web to the xen server the virtual machine is hosted on. This is done on the local network, users do not need port 5900 access to anything!

Users can open multiple consoles at the same time in the same session


Xen Cloud Platform proved to be a stable and robust competitor to the other enterprise level virtualization options that are currently offered

Offers a low cost (hardware only) highly scalable solution to server virtualization, and allows for the creation of Windows, Linux, and
FreeBSD guests

Virtual machines can be accessed securely from anywhere via web browser

VLANs allow separation for security


Lab environments can be consolidated

Students can each have their own set of virtual machines rather than sharing physical computers, maximizing their learning experience


Xen Overview: http://xen.org/files/Marketing/HowDoesXenWork.pdf

Citrix XenServer 5.6 Feature Pack 1
Administrator's Guide: http://support.citrix.com/article/CTX127321

Xen Cloud Platform: http://xen.org/products/cloudxen.html

Citrix XenCenter: http://community.citrix.com/display/xs/XenCenter

XVP Appliance: http://www.xvpsource.org/topic=about&page=xvpappliance


My notes, paper, and a copy of this presentation can be found at: http://ronnybull.com/portfolio/masters-project

Within my notes all of the setup commands are documented with step by step instructions.
Source code for my scripts are also included for bug workarounds.