Terminal Servers
30 June 2002

Thin clients, diskless workstations, terminal servers.

So here's the idea: take one of the old PCs, throw out the old hard drive, forget about the tiny amount of memory and rip out the fans, since the programs won't be running locally anyway. All you need is an interface between your monitor/keyboard/mouse and the server. To get going, you use etherboot -- a 16kB bootcode in the EPROM network card.

As the LTSP instructions put it, "Utilizing the LTSP, you can take very low-end PCs, remove the hard drive, floppy and CDRom, and add a bootable network card. Many network cards have bootrom sockets, just waiting for a bootrom to be inserted. During the boot phase, the diskless workstation obtains its IP info and a kernel from the server, then mounts the root filesystem from the server via NFS."

This may be the one thing that you need: bootrom in the network card. You also need to make sure that you can run all apps remotely -- the way to prepare for this would be to start doing it!

The instructions are excellent -- quite unusually good for Linux -- but they are complex and it will take a couple of days at least to get this going. That means you shouldn't even think about it until the dissertation is done.

See ramdisk for details on how to do that.

29 July 2003: There's a package in Debian called etherboot that should work for this -- "Bootstrapping for various network adapters.  Etherboot is a free software package for making boot ROMS for booting Linux and other operating systems on x86 PCs over a network using Internet Protocols, i.e. bootp/DHCP and tftp."

Main Linux software sites

• Net booting a Linux workstation
• Remote Network Boot via PXE
  
• Linux Terminal Server project -- http://www.ltsp.org/index.php
  • Download -- http://sourceforge.net/project/showfiles.php?group_id=17723
  • Instructions -- http://www.ltsp.org/instructions-3.0.html and
    
    • http://prdownloads.sourceforge.net/ltsp/ltsp-3.0.pdf?download
• Thinguin -- http://www.thinguin.org/
• Etherboot -- http://etherboot.sourceforge.net/
• Etherboot mailing list -- http://www.geocrawler.com/archives/3/5299/
• A database of Etherboot-compatible ethernet cards -- http://etherboot.sourceforge.net/db/
• ROM-o-matic dynamically generates Etherboot ROM images -- http://rom-o-matic.net/
  
• PXES -- Linux for thin clients -- http://freshmeat.net/redir/pxes/28219/url_homepage/
  • Sketch at http://www.icewalkers.com/softlib/app/app_01619.html
• Diskless workstations (LTSP hardware sales) -- http://www.disklessworkstations.com/
• Win4Lin emulator -- running windows applications in a Linux server

More information

http://www.ltsp.org/documentation/mandrake_ltsp.html

http://www.rom-o-matic.net/5.0.4/ == choose natsemi for gubbio

http://etherboot.sourceforge.net/db/ -- is your card(s) listed?

Gubbio's Nic is a Netgear FA312.
chip: dp83815
wake on LAN: yes
ROM type: likely eprom
Interface type: likely TP

National Semiconductor cards

http://www.thinguin.org/news.html
28 May 2001
Etherboot driver for National Semiconductor DP83815 Ethernet controller released. This driver supports Netgear FA311/FA312 NICs. You can generate ROMs using http://www.rom-o-matic.net/5.0.1-mc1 and http://www.rom-o-matic.net/5.1.0-mc1 Here is a patch file for adding this driver to other versions of Etherboot.

Here is the source code:
http://www.rom-o-matic.net/5.0.1-mc1/src-5.0.1-mc1/natsemi.c

It may be that the wake-on LAN is the eprom chip?
A sales site mentions a 3 pin LAN Wake cable -- ??

tech specs: http://etherboot.sourceforge.net/db/nics.php?show=tech_data&vendor=Netgear
Real specs: http://www.netgear.com/product_view.asp?xrp=1&yrp=1&zrp=6

The Simplest Way Of All

(The problem is, I'm not using xdm.)

X-terminal Mini HOWTO: Version 1.0

Published by LinuxOrbit.com, October 7, 2002
By Andrew Casey, a.k.a. Drewbian

Want to make a thin client to connect to your main computer ? All you need is a network and a second computer that is capable of networking and of running X.

This Mini-HOWTO assumes you already know how to setup X, Linux and or a *BSD system and a network.

For my setup I used a pentium100 with 16MB of RAM, 200 MB hard drive and an NE 2000 ISA network card (a pentium 100 is probably overkill, a 486dx2 66 should be enough).

Install a small linux or BSD distribution with X onto your X terminal machine ( I would recommend Debian Potato) making sure you install the appropriate X server for your video card and some extra font packages (you won't even need a window manager). You will then have to setup the network and XFree86 (consult the documentation that came with your distribution of choice).

Next, on your main machine install xdm (x display manager) and then change directories in a terminal window with the command:

(the location of the xdm config files may differ, depending on your Linux distribution). Then as root, open the file Xaccess and put in the ip of your xterminal box. Then open xdm-config and comment out the displaymanager requstport line like this:

(placing a "#" symbol in front of the line comments it out).

Once you've made these changes, start xdm on the main machine and then on the X terminal start X with the command:

You should then (hopefully) see the xdm login of your server displayed on your X terminal. Login as your username on the X-server (or better yet a user account you have created for the task).

Caveats: There are some major security issues running X over a network in this manner. As the X protocol is not encrypted any passwords you enter on the xterminal will be sent across the network in plain text !. You have been warned.

Source.

A Short Guide in German

A German site first put me on the track that in Linux, the typical thin client is a discarded PC. This site is focused on using such systems in schools.
http://www.linuxfreunde.de/marl/medienecke.html

Die Schüler-Arbeitsplätze (Clients): Die Arbeitsplätze sind extrem wartungsarm und leise, sie benötigen keine Festplatte und oft auch keine aktive CPU-Kühlung.

Client - Hardwareausstattung: 486er oder Pentium PC, 8-16MB RAM, 1MB Grafikkarte, Netzwerkkarte, Maus, Tastatur, Monitor Nicht erforderlich aber nutzbar: Festplatte, Diskettenlaufwerk, CD-ROM, Soundkarte

Client - Softwareausstattung Etherboot = 16kB Bootcode im (E)PROM der Netzwerkkarte oder auf einer Diskette

This is what needs to happen: Im Client ist eine Netzwerkkarte mit Boot-Prom installiert, statt Boot-Prom kann man auch einer Boot-Diskette verwenden. Nach dem Einschalten sendet der Client ein BOOTP-Broadcast. Der Server erkennt den einzelnen Client anhand der Ethernet(MAC) Adresse des Clients. Per DHCP & tftp bekommt der Client seinen Betriebssystem-Kern, ein minimales Linux, Das Linux auf dem Client mountet sein root-Filesystem per NFS von Server. Alle Clients verwenden dasselbe, per NFS freigegebene Verzeichnis, stören sich dabei aber nicht, weil keine Schreibzugriffe erfolgen. Der Client startet einen für seine Grafikkarte, Maus & Monitor konfigurierten X-Server, welcher dann eine XDMCP Anfrage an den Server sendet. Der Server sendet ein graphisches Login-Fenster. Dieser Vorgang dauert zwischen 30 und 60 Sekunden.

Nach einer Sitzung ist es nicht unbedingt nötig sich vom Server abzumelden. Der Client kann jederzeit gefahrloss ausgeschaltet oder resettet werden.

Auf dem Server müssen folgende 4 Dienste konfiguriert und gestartet sein: tftp, DHCP, xdm(oder kdm,gdm), NFS

Hardware

Instead of using an old PC, you could shell out between $300 and $500 and get a sleek little connector on your desk, the size of a book.

Overview
http://www.thinplanet.com/

Less than $500
http://www.thinplanet.com/trends/sub500.asp

Wyse Winterm 5440XL, a Linux-based thin client for $519
http://www.thinplanet.com/trends/wyse.asp

The Winterm 5440XL is based on SUSE Linux
http://www.thinplanet.com/news/generic.asp?v=NE10564

Wyse Winterm 1200LE for $299
http://www.adtcom.com/Wyse/Wyse_1200LE.htm
http://www.cdw.com/shop/products/default.asp?edc=263272

Note that it has two USB ports in addition to the Ethernet card. You should be able to just plug it into your small ViewSonic.

Lots of thin client prices -- not all Linux:
http://www.nextag.com/Thin_Clients~nz300358z5z15z44z6fq1zi4zmainz5-htm

Neoware Systems Eon 4000
http://www.neoware.com/

Neoware Capio 504 TC Linux ICA W/ Kybd MSE for $290
Integrated network, graphics, and sound cards; PS/2 style keyboard & mouse; HD-15, DB-9, and DB-25 graphics port. And on model 508, you can even use USB floppy, Zip, or CD-ROM drives
Specs at http://www.neoware.com/products/capio/5xx.html
Buy at http://www.pagecomputers.com/cgi-bin/page/S1005707.html

This actually looks really attractive, as does the next one:

IBM NetVista N2200 THIN CLIENT 96MB ETHERNET for $299.97
Manufacturer Part #8363GUS, TurboLinux certified
Sound, microphone, headphone, USB, Ethernet, HD-15
http://www2.warehouse.com/product.asp?pf%5Fid=CP18285&dept%5Fid=&cat=

Openbrick

http://openbrick.org/ -- for thin client. There's a Debian version. OpenBrick is a small, light and silent open platform optimized for Open Source / Free Software solutions (firewall, micro-server, PABX, thin client, multimedia...).