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[ K12LTSP.org | Downloads | Installation | Configuring Server | Configuring Clients | FAQ's & More ]
Installation Checklist:
 This tutorial will cover the installation of the K12LTSP terminal server. See the Installation Guide for other installations.

Server Hardware: There are two ways to implement your LTSP server: A single classroom server for 2-10 workstations or a large lab or building server for 20-30+ workstations.
Classroom Server 5 clients
Lab or Building Server 10+ clients
  • CPU: One PIII 1 gig or faster
  • RAM: 512mb + (50mb for each client)
  • HD: ATA/100 10+gig IDE
  • Network: (2) 100/base cards and a 100base hub (8 or 16 port)
Comments: Today's new workstations are perfectly suitable for powering 2-5 thin-clients. See our classroom tour page for an example of this solution. You can get by with slower computers, but once you get used to the speed it's hard to go back!

Note: A K12LTSP server also makes a perfect cable modem gateway/firewall and household terminal/file server.
  • CPU: Two or more PIII or Xeon processors. AMD now has dual Athlon solutions but we have not tested any. (Offers?) ;-^)
  • RAM: 2gig or more (512mb + 50mb for each client) More ram = more speed
  • HD: UW SCSI drives, one for applications and one for /home
  • Network: (2 or more) 100/base cards and 100base hubs/switch (16 or 24 port, switches are much faster with more clients)
Comments: RAM - More is better One thing is clear when using K12LTSP and Gnome or KDE, you'll need ram. This is especially true if you're running OpenOffice. More ram will make your server faster as frequently used files are cached. Too little ram will bring your server to a crawl as it starts swapping memory to the hard dirve. If you run out of memory, performance will be unacceptable.

Using LTSP for large numbers of clients successfully depends entirely on how the workstations are used. Any solution will be hard pressed to answer requests from 30 students all launching applications at the same time while workstations spread around the building will rarely be active all at the same time. One server can easily handle 30+ clients in this case.

SCSI is faster than IDE: We've seen LTSP servers slow to a crawl when more than 10 clients are running from IDE drives. SCSI drives are better equipped to handle the multiple read/write requests. This is especially true for /home folders. Running the K12LTSP server from an IDE drive with an NFS mounted /home share works fine.

For large lab installations it's better to spread the load over 2 or 3 servers. Our high school's 100+ thin-clients use 4 modestly powered servers instead of one large one.


 
Ethernet Cards, Hubs

Your server will have two ethernet cards, one to create a private network (192.168.0.x) on a hub for terminals and one to connect to the rest of your network.

You can install LTSP servers with just one ethernet card. They will then live on your network and be available from all over your school. For single card installations we've prepared a list of files to edit to help you with your network settings.

By default the LTSP sever runs DHCP on the client's card (eth0) and automatically gives out IP #'s upon request. It then accepts bootp and PXE boot requests and passes on the Linux kernel to the client. The default dhcpd.conf file will support over 200 clients. All this happens on eth0. The LTSP server will not answer dhcp requests over eth1 (with the default settings.)

Why do we default to a private network and 2 ethernet cards? Thin-clients and servers can generate a lot of network traffic. By isolating this traffic on a single hub and routing only necessary traffic out to the rest of the network we lower the overall impact of clients on school networks that are often substandard in the first place.

server diagrahm


Tip : Our classroom LTSP servers are connected to the rest of our school via 10base ports. We NFS mount /home over eth1 and run the clients from a hub on eth0. This works well and gives us a configuration we can easily replicate throughout our building.

Planning Your Network

It's a good idea to gather some information before you start installing Linux. If you simply click "Next" and "Yes" straight through the install after selecting "LTSP Server" you'll end up with a working server ready to go.

If you are planning on using static IP addresses and/or just one ethernet card then you'll need to gather some information on your network. See the list of files to edit at the end of this page.
 		 You can skip all this if you're doing a default install. Just plug eth1 into a port and if you have DHCP running on your network your server will be up and running. Connect eth0 to a hub for clients and you're ready to go!


 One or two network cards?
DHCP or static IP numbers?
Classroom server or building/lab server?
Hostname of server?
DNS server?
Gateway?
Netmask settings?
etc...


Installation Choices

  • LTSP - Creates a terminal server for thin-client workstations. Server defaults to an IP gateway/firewall when 2 ethernet cards are present.
  • Workstation - Installs all the workstation applications and a stand-alone, workstation version of Red Hat 8.
  • Server - Installs common server applications and skips the graphical goodies. Use this option for file, print and web servers. Note that you will only have a command line interface with the server option.
  • Custom - This option lets you pick and choose. You can mix and match applications. Don't use this option if you're a newbie.  ;-)  

For our LTSP install select "LTSP."
 install options
Click for larger image...

Note: Screen shots and notes on all the options are available in the Installation Guide.

 
Network Configuration

eth0 is the interface on the thin-client side of your LTSP server. You will connect this network card to your terminal hub. The 192.168.0.x address is designated as a "private" IP address for internal networks. IP traffic from you clients are routed to the Internet and the rest of your network through eth1.

Note that the server has the last available address in this range, 192.168.0.254. The first client will be assigned an IP # of 192.168.0.253.

You won't have to enter hostname info or any of the information in the lower half of the window. These settings will come from eth1.

The default for eth1 is "Configure using DHCP." If you are using custom settings then you'll need to click on the "eth1" tab and configure the card.

If you're only using one ethernet card then go ahead and enter the information in the bottom part of this form

Remember that all of this information can be edited later with the standard Red Hat network configuration tools.
network settings


NOTE: K12LTSP 4 does a much better job of configuring your system with non-default IP settings. If you do run into trouble, check these files when using a single ethernet card LTSP install:

You'll have to look through these files and replace 192.168.0.x with the appropriate IP network information for your network.

 
    /etc/exports
    /etc/hosts.allow
    /etc/rc.d/init.d/nat
    /etc/hosts
    /etc/dhcpd.conf
    /opt/ltsp/i386/etc/lts.conf
    /opt/ltsp/templates/k12linux/hosts-update.sh
    /opt/ltsp/templates/k12linux/setup-update.sh


For the rest of the install I think you'll be fine using the Installation Guide . This is a great resource complete with screen shots and good explanations of all the options.