Medusa Project

Medusa Project Implementing LTSP at SF State University Sameer Verma, Ph.D. Bo Kim

Thank you!
Bo Kim – taking up the challenge
Jack Tse and Don Strickler – loaning us a switch
Tony Chan and Karl Schackne (BUS computing) – for letting us use the lab.
Edubuntu team – making an excellent LTSP distro!

Overview
Brief introduction to LTSP
Requirements for running LTSP
Advantages and disadvantages
Medusa - LTSP at SF State
Possible implementation scenarios
Informative links

What is LTSP?
Linux Terminal Server Project
Allows “thin” clients to connect to a Linux Terminal Server.
All programs run on the server
Clients run a thin Linux base with network and X session capabilities.
LTSP allows for a single point of configuration and control
Great for lab environments

A “thin” client performs a Preboot Execution Environment (PXE) boot and retrieves an IP from the LTSP server via DHCP.
dhcp server runs on the private network interface on the LTSP server
DHCP response PXE DHCP request How it works

How it works
A small footprint Linux kernel is sent to the thin client computer via TFTP.
The client loads the Linux image and starts the X window system via secure shell (ssh)
client images and server have ssh keys
X session forwarded over ssh DHCP response + TFTP Linux image

How it works
All programs execute in a X session on the server, but are forwarded via ssh and displayed on the thin client.
Feedback from the user (keyboard & mouse) are sent back to the server over ssh as well.
X session forwarded over ssh mouse+keyboard

What Does it Look Like? 192.168.0.0/24 eth1 eth0 firewall SFSU 130.212.14.0/24

Hardware Requirements
Server
CPU should be powerful enough to run multiple X sessions.
Intel Xeon processor.
75-150MB of RAM per client.
2 Network Interface Cards
Private interface preferably gigabit
Clustering?
Not sure if it is possible

Hardware Requirements
Client
Minimum
Pentium II with 48 MB RAM and a 2MB display card.
Recommended
Pentium II and above with 64MB RAM and 4MB display card.
Identical hardware preferred

Networking Requirements
Network
Avoid
Hubs
10-BaseT cards
Preferred:
100 Mbps switch
100-BaseT cards
Ideal:
Gigabit switch.
100 Mbps switch with 1 Gbps uplink to the LTSP server.

Software Requirements
A Linux distribution with or without LTSP included.
LTSP (if not installed natively)
Most distros except Ubuntu and Debian do not have LTSP 5.
LTSP 5 is significantly different
LTSP 5 builds thin-client environment off of the server environment.

Software Requirements
Four services running on the LTSP server:
DHCP for IP address leases
TFTP for initial netboot kernel
NFS for forwarding filesystems
SSH for all communication on the LAN
Note: Ubuntu does not use XDMCP. It uses X forwarded over ssh instead

Advantages
Diskless clients
Highly Centralized
patches
firewalling
Cost effective
no licensing fees
Customized profiles
LDAP auth
Change lab footprint as needs grow
Invest in powerful server
Need a fast network
Documentation is weak
Many references to LTSP 4.x
Sabayon seems broken in Ubuntu Feisty.
Time sensitive apps will not work well, especially multimedia
Disadvantages

Medusa Project
LTSP server
Note: Single processor, but appears as two

Medusa Project
10/100 Mbps unmanaged switch
20 clients
Dell Optiplex
Pentium 4
256MB RAM
15 inch flat panel
Some have speakers

Medusa Project
Edubuntu – Ubuntu for Education
Additional software installed:
Webmin
Firewall/NAT
Sabayon
Customized user profiles and lockdown (built-in, via pessulus) tool.
Seems to be broken in Ubuntu Feisty

Medusa Project
Captured CPU, RAM, Swap and NET behavior
We looked at behavior with one and multiple users (1+8) on the LAN.
Note: We did not use a built-in screen capture program because it muddies the parameters. We used a video camera instead.

Medusa Project CPU NET RAM SWAP All clients at login screen

Medusa Project CPU NET RAM SWAP One client starts Firefox

Medusa Project CPU NET RAM SWAP One client starts OOo

Medusa Project CPU NET RAM SWAP Multiple clients start OOo

Medusa Project CPU NET RAM SWAP First client starts video

Medusa Project CPU NET RAM SWAP Multiple clients start video

Medusa Project CPU NET RAM SWAP Multiple clients finish video

Medusa Project CPU NET RAM SWAP All clients logout

Services at the LTSP Lab
Dual boot
Windows XP localboot, Ubuntu Linux via LTSP.
Both environments get dhcp and firewalling via LTSP server.
Note: Lab machines will be on a private network
Administrator can maintain lab logs for accounting

Services at LTSP lab
Internet access
Office Automation
OpenOffice
Graphics
GIMP
Inkscape
Scribus
Printing via network

Thin Client Manager

Webmin

Future use at SF State
Domain Authentication
Users will be able to use their SFSU accounts to logon via LDAP
Traffic Shaping
More efficient network load balancing that will be conducted on the LTSP server.
Support Windows apps via Win4Lin or VMWare
Possible to boot PPC thin clients

Informative Links
www.ltsp.org
http://en.wikipedia.org/wiki/LTSP
www.edubuntu.org

Demo time…..

Questions?

Medusa Project

by Sameer Verma

Accessibility

Categories

Upload Details

Usage Rights

2 Embeds 239

Statistics

Medusa Project Presentation Transcript

http://opensource.sfsu.edu	238
http://www.babelfish.altavista.com	1