Virtual Computing LaboratoriesPast, Present, and Future

 Stephen D. Burd

Associate ProfessorProvost’s Academic Technology Liaison

burd@mgt.unm.edu

Last Revised: 04/19/2023 08:43 PM

Acknowledgements

Others that have and/or continue to work with me on VLAB-related issues Alex Seazzu – Faculty member and ASM IT services director Greg Gaillard – Manager of infrastructure and services –

including the ASM VLAB Josh Saiz – Application developer and database manager,

adjunct faculty member, and VLAB user in multiple courses Eugene Rooney – Application developer, VLAB web portal

developer, and adjunct faculty member Kara Nance – Faculty member and VLAB developer/user at the

University of Alaska Fairbanks Brian Hay – VLAB developer and manager at the University of

Alaska Fairbanks Ronald Dodge – Faculty member and VLAB developer/user at

the United States Military Academy

Definitions

Virtualization Simulating one type of computing resource with another, for example

Virtual memory - using disk as a RAM extender Hardware abstraction layer - emulating an Intel CPU and chipset with software executing on a

POWER CPU

Technique for making the sum of allocated computing resources appear greater than actual physical resources

Virtual computing environment (VCE) Software that enables simulating one “complete” computing environment Examples: VMware Workstation or ESX, Microsoft Hyper-V, Apple Parallels, Xen Combines earlier “single resource type” virtualization approaches into an integrated

whole Today, the term virtualization is synonymous with the use of VCEs

Virtual machine (VM) A single simulated computing hardware environment with network connections/services

and installed system and application software (e.g., a virtualized workstation or server)

Configuration Multiple VMs operating on a virtual network with or without network services (e.g.,

DHCP) and connected to or isolated from other networks

Resurgence of Virtualization

VCEs were widespread in the 1960s but faded by the early 1980s IBM 370 and 3090 systems used virtualization to share a single

mainframe between batch and online operating systems IBM AS/400 operating in System 36 emulation mode was one of the last

commercial implementations in that era

VCEs made a comeback in the late 1990s – Why? Reduced cost disparity among desktops, minicomputers, and “big iron” CPU cycles in abundance Fast networks and consolidated storage Reduced management complexity and total cost of ownership (TCE)

Usage scenarios: Software testing (single machine) Server consolidation Desktop virtualization Complex test environments containing multiple VMs on an isolated virtual

network

What is a VLAB?

VLAB = Virtual computing laboratory The virtual equivalent of a physical computing

laboratory in an educational setting Users access hardware and software resources without

being “in the same room” as the physical resources Shared multiuser resources (e.g., server clusters)

emulate single-user resources (e.g., desktop computers)

Resources may be general-purpose or customized to specific educational needs

Resources are updated and reconfigured to match changing needs

Sample Educational VLABs

University Description URLGeorge Mason University

Apache VCL, general purpose computing laboratory, similar labs implemented at other Virginia state universities

http:// www.vcl.gmu.edu

Georgia State University

Apache VCL, primarily supports students using SPSS and similar software

http://www.gsu.edu/help/46646.html

GENI Citrix Xen with significant extensions, supports advanced research into distributed applications

http://www.geni.net

SUNY - Buffalo Citrix XenApp, general purpose computing lab, also provides access to common data storage

http://ubit.buffalo.edu/software/virtual/index.php

University of Alaska - Fairbanks

VMware ESX and Lab Manager, provides specialized labs for information assurance courses.

http://assert.uaf.edu/lab.html

University of Maryland

Citrix XenApp, primarily supports engineering students http://eit.umd.edu/vcl

University of New Mexico (UNM)

VMware ESX and Lab Manager, provides a general-purpose computing laboratory and specialized labs for information systems and information assurance

http://vlab.mgt.unm.edu

University of North Carolina

Apache VCL, general purpose computing laboratory, similar labs used at other NC state universities

http://vcl.unc.edu

University of West England

Citrix XenApp, general purpose computing lab, also provides access to a common data storage

http://www.uwe.ac.uk/its/corporate/services/remotefiletransfer.shtml

Common VLAB Usage Scenarios

Scenario Details UsesApplication virtualization

One or more applications (e.g., SPSS or Microsoft Office) hosted on server with presentation layer executing on user device

General-purpose computing and license sharing

Stateless desktop virtualization

Complete VM with operating system and applications hosted on server with remote console on user device, VM initialized to default state each time it is used

General- and special-purpose computing

Stateful desktop virtualization

Complete VM with operating system and applications hosted on server with remote console on user device, per user VM state is stored between uses

Longer-term projects, configuration exercises

Multiple VMs with virtual network

Multiple VMs (e.g., servers and clients) interacting within a private isolated network (usually with state retention)

Advanced computer-related courses and projects

Educational VLAB BenefitsThe Sales Pitch

Support learning at a distance Reduced hardware and space costs Efficient use of lab, site, and academic licenses Minimal investment required of students Simpler management (of some things) Support for complex hardware/software

environments Specialized configurations per course or assignment Multi-machine configurations with customized networks Fast/simple setup and tear-down A protected sandbox for “dangerous games”

UNM VLAB Implementations - Past

VLAB version 1 (2005-2008) Rack of ordinary workstations

connected to a SAN (see image on right)

Custom-developed Web portal + remote desktop protocol (RDP)

42 users – one per computer

VLAB version 2 (2008-2010) 4x Dell 2950s (32 CPU cores, 128 GB

RAM) 2 TB storage array VMware ESX v3 + vCenter Lab

Manager v3 Ordinary web server for portal Client console interface via ActiveX

browser plug-in Up to 100 users and scalable to more

UNM VLAB Implementation – Present

VLAB version 3 (2010-2013) 3x Dell R910s (32 CPU cores,

512 GB RAM each node) 6 TB storage array VMware

ESX v4 vCenter Lab Manager

Same web server and ActiveX console interface

Up to 400 users?

Version 3a (early 2013) Migrate ESX to ESX 5.0? Add a few more network

interfaces?

VM-Based VLAB Architectural Overview

Quick VLAB Demo

VLAB Challenges – The Gotchas

Acquiring, configuring, and supporting the VCE and its underlying physical resources

Limited I/O efficiency Clunky user interfaces – portal and VM console More complex management (of some things) Student and faculty training and support

Current Network Issues

Acceptable performance requires High-bandwidth and low-latency Internet connections at

both ends – particularly problematic at the user end Avoid I/O-intensive applications and features (e.g.,

complex desktop backgrounds, transparency, and motion-video) to minimize bandwidth requirements

Need high-performance connections among compute, storage, and network resources

Current User Interface Issues

VMware Lab Manager is misnamed! Not really designed for an educational computing lab

Better suited to “professional” administration of virtual servers

All the shortcomings of a Web-based application, e.g., Click, wait for refresh, click, wait for refresh, ... repeat ad

nauseum Lacks many standard desktop capabilities such as drag/drop,

limited support for other such as cut/paste

Non-intuitive interface and terminology for end-users (e.g., workspace, template, configuration, clone, deploy, and undeploy)

“Atomic” actions from the student or faculty perspective require multiple steps with many “traps for the unwary”

Browser Support

Limited browser support Internet Explorer with an ActiveX control works best Firefox also works

Customized browser and firewall configuration Enable/accept ActiveX download Disable Internet Explorer protected mode Add lab manger URL to trusted sites list Open 90x ports

Library Management

Faculty and/or technical staff typically manage a library of VMs and configurations: Standard VM provided to all users for general-purpose needs Many courses use a single VM with all needed tools (e.g., Office

+ Visio + Visual Studio for a database course) Some courses use multiple VMs alone or in a configuration

Library management issues: Creating VMs and multi-VM configurations is complex and time-

consuming Complex classes (e.g., information assurance) may have dozens

of VMs and multi-VM configurations No tag, index, or search capabilities (so, is it really a library?) Sharing VMs and configurations across classes and faculty is

cumbersome – OUs are hierarchically related with no inheritance

User Management

User management issues: Large classes and general-purpose lab access require

managing hundreds to thousands of user accounts Lab manager can be configured to use “internal” accounts –

best avoided! User account import from LDAP or Active Directory is

straightforward though not for non-technical faculty and staff Doesn’t use LDAP or Active Directory as a central authentication

service

Implementing access controls requires management of groups, permissions, roles, and resource pools - beyond the skill of non-technical faculty

Accounts and groups must be defined and redefined from semester to semester

Resource Management and Overall VLAB Performance

RAM and disk are usually the most limited server resources VMs must economize on both or overall VLAB performance suffers Economization can be complex and may require usability or suitability-to-purpose compromises

(e.g., older OS version or disabled features in newer OSs)

VM and template management VM templates can be created and cloned to a library or workspace Cloning creates long dependency chains and a trail of linked disk image and delta files that

compromise performance (due to more complex disk I/O) Shortening dependency chains

Improves VM and overall VLAB run-time performance Requires lots of disk space for “full” clones Increases administrative effort

In an Active Directory environment clones can’t be “on domain” unless their GUIDs are modified – which may break preinstalled software and services

VM existence and deployment duration “Throw-away” VMs are best since they consume no resources when idle

But, they must be cloned from a library or template before each use – a delay

Many educational activities require longer-lived VMs and configurations that consume disk resources even when not deployed

Need to balance more immediate access but greater resource requirements of long-lived always-deployed VMs against the lower resource requirements but delayed access implied by cloning and deploying – available resources vs. user patience

Training and Support Requirements

There are two significant resource requirement increases when using a VLAB User support for faculty and staff

Student and faculty training to navigate Lab Manager and deal with browser configuration issues – significant even for “technically-savvy” users

Additional training for faculty to self-manage libraries and users Help desk support

Technical staff Acquire, configure, and manage back-end resources Acquire, configure, customize, and manage the front-end Configure and manage “general-purpose” VMs Perform class-related tasks that faculty are unwilling or unable

to perform

UNM VLAB Implementation - Future

Primary drivers for change VMware Lab Manager reaches end of life in June 2013 Current hardware architecture has reached limits Want to explore cloud-compatible approaches Want greater access from non-Windows devices Want an easier-to-use interface for students and faculty

Dell will supply new hardware for VLAB experimentation Blade architecture with a 40 Gbps backplane Fractional provisioning of CPU, storage, and network resources We’ll partition it into at least two pieces to experiment with different VLAB architectural

approaches

VLAB experimental version 4a vCloud Director 1.5 ESXi 5.0 VMware View?

VLAB experimental version 4b Windows Server 2012 Hyper-V and Windows desktop virtualization services Library, configuration manager, and portal – to be developed

Market and Technology Trends

Migrating to the cloud Migrate what, precisely? Migrate using which supporting technologies/products? Private cloud, public cloud, or both?

End-user devices Fixed workstations Mobile workstations (keyboard, touchpad and/or

mouse, and “large” screen) Tablets (no/optional keyboard, touch screen, and

“midsized” screen Handheld (e.g., smart phone)

Market and Technology Trends - Continued

How to access virtual software, data, and services on end-user devices As in current VLAB architecture – complete VM

executing on a server with a remote console Local execution of VMs (e.g., Windows 8 with HyperV

or Parallels/BootCamp on a Mac, VM downloaded or distributed on a flash drive)

Application streaming (e.g., Citrix, Microsoft App-V, VMware ThinApp)

Web applications (e.g., Office 365 and GoogleDocs) Cloud storage (e.g., SkyDrive)

Market/Technology Trends - Observations

Virtualization and VLABs are here to stay for the foreseeable future Virtualization support hardware is wired into CPUs Virtualization is a standard feature of latest client OSs and will likely migrate to “lower”

platforms like tablets and smart phones Distance education is growing Users expect anywhere/anytime access to every education resource

Back-end tools and infrastructure for application and desktop virtualization deployment are well-developed Nearly mature technology Available from multiple vendors Still some variation in support for host hardware and OS environment Rapidly migrating into the cloud

Application virtualization and software as a service are also well-developed, though there’s room for improvement and standardization

Mixed environments that deliver resources via a combination of methods are feasible (e.g., Office via SAS, Adobe Creative Suite via app streaming, and developer toolkits encapsulated within complete VMs) Using, administering, and supporting them may be overload for both users and technical

staff

More Observations

Cloud-based VLABs (VLABs as a service) are a natural progression forward Management and security issues will become more important than

technology and accessibility issues App-streaming and stateless-desktops will probably be first,

followed later by stateful desktops and multiple-VM configurations Streamed apps and virtual desktops will need to integrate

seamlessly with cloud storage

Lab administrators will have to determine which apps/desktops/services can be supported on which clients Some software and services will easily move from desktop to laptop

to tablet to phone (e.g., many office apps) Some software and services will be limited to devices with sufficient

screen size and I/O flexibility (e.g., users can’t feasibly interact with current programming toolkits via a tablet or phone)

Current VM-Based VLAB Infrastructure Alternatives

VMware ESX + vCloud + View Industrial strength product with a long track record Strong support for Windows and UNIX VMs and clients Apple client support is a recent addition Portal environment?? Unclear what is Lab Manager successor – possibly third-party solutions

(e.g., Liquidware ProfileUnity FlexApp) Strong support for virtual networks and multiple-VM configurations

Windows Server 2008/2012Microsoft Hyper-V Hyper-V bundled with server OS and embedded in Windows 8 Strong support for Microsoft clients/servers and UNIX servers Adequate support for UNIX and Apple clients via RDP Portal environment can be provided through IIS and bundled desktop virtualization tools –

unclear how well they fit an educational VLAB environment Support for virtual networks and multiple-VM configurations?

Apache Virtual Computing Lab Linux/Xen virtualization and VM deployment – Open source Strong support for Linux and Windows VMs Strong support for UNIX, Windows, and Mac clients via RDP Apache web server and tool-kit for portal development – some templates provided through IBM Weak support for virtual networks and multiple-VM configurations

Sample Cloud-Based VLAB Solutions

IBM Cloud9 Xen-based desktop virtualization Relatively complete solution

Dell Virtual Labs Suite of products/services targeted to educational uses App streaming products/services use Citrix XenApp or VMware View

infrastructure with thin clients Integration of Dell hardware and setup support services with third-party

infrastructure

Nimbus Open-source Xen-based VM deployment to third party cloud providers Targeted to scientific and high-performance applications

GENI Xen-based VM deployment to local and remote server clusters (of member

institutions) across configurable/experimental I2/LR connections Targeted to research applications for next-generation network and distributed

software architectures

Summary

VLABs do deliver on their benefits, but not without significant costs and some limitations

Current VLAB technology can’t deliver the same experience to all users all of the time as sitting in front of a directly-connected console

There are multiple implementation alternatives, but nothing yet comprises and “out of the box” solution for local installation

IBM Cloud9 is the best-developed cloud-based VLAB service

Successful VLAB implementations require lots of training, user support, and technical staff resources