Installing LTSP server on Ubuntu 10.10

LTSP – stands for Linux Terminal Service Project. LTSP is a software package, when installed on a Linux server, lets Thin clients to connect to LTSP and run applications that are processed on Server. So what is a Thin client? It`s a regular workstation that can be booted up from network. Client can be booted also by local boot device (like a harddisk, CD-ROM or USB disk). But I will talk about network booting. And how does it work? Workstations is configured to boot from network, in order to boot your network card must support Preboot Execution Environment (PXE) or NetBoot.

LTSP looks something like this: LTSP overview

Picture from https://help.ubuntu.com/community/UbuntuLTSP/LTSPWiring

It works as fallow:

  1. The client first requests its IP address for the LTSP server via DHCP and loads the Linux kernel from a preconfigured Linux image on the LTSP server via the Trivial File Transfer Protocol (TFTP) service running on the LTSP server. During this process the client makes a (new) DHCP request for the IP address of the LTSP server and the path to its chroot environment. When this information is retrieved, the client mounts the path on its root filesystem via either the Network File System (NFS) or Network Block Device (NBD) services running on the LTSP server.
  1. The client loads Linux from the NFS mounted root filesystem (or NBD filesystem image) and starts system. The client connects to the XDMCP login manager on the LTSP server.
  2. User logs in and uses system

For LTSP to run on server need to be running 4 services:

  1. DHCP – Dynamic Host Configuration Protocol: used to lease IPs to clients.
  2. TFTP – Trivial Transfer File Protocol: to transfer files to clients, like the client software.
  3. NFS – Network File System: used to mount remote directories. NBD – Network Block Device: used to mount remote storage devices.
  4. XDMCP – X Display Manager Controller Protocol: used to implement graphical login displays.

Why to use such a system?

Well LTSP is very popular in use in schools and one good think is that system can run on low end PC and life cycle of such a pc can be up to 10 years which offers great saving. Also an educational institution may also gain more control over how their students are using computing resources by switching to a thin client configuration.

Some examples of distributions using LTSP are AbulÉdu, Edubuntu, K12LTSP and Skolelinux.

How to set up LTSP quick guide.

In Linux terminal type this commands:

  1. sudo apt-get install ltsp-server-standalone openssh-server
  2. sudo ltsp-build-client or if your on a 64-bit system with 32-bit machines do sudo ltsp-build-client –arch i386
  3. for editing the server’s IP values use /etc/ltsp/dhcpd.conf
  4. after that you need to restart DHCP server  – sudo /etc/init.d/dhcp3-server restart
  5. and update sshkeys -sudo ltsp-update-sshkeys
  6. and if you updated dhcpd.conf then you need to update you image also by typing in terminal ltsp-update-image

Resources:

http://en.wikipedia.org/wiki/Ltsp

http://sourceforge.net/apps/mediawiki/ltsp/index.php?title=Main_Page

http://linux4dummies.wordpress.com/2007/06/29/ubuntu-ltsp-server/

Advertisements
This entry was posted in week 4. Bookmark the permalink.

2 Responses to Installing LTSP server on Ubuntu 10.10

  1. Abdul Wahid says:

    Hi,I have follow the procedure as told but when i run my dhcp server then it run successful but client show an error such as follows:
    Error:

    PXE-E51:No DHCP or proxyDHCP offers were received.

    PXE-M0F: Exiting Intel Boot Agent.

    Boot Failure

    And content of my etc/ltsp/dhcp.conf file is as follows

    =============BOF===========
    #
    # Default LTSP dhcpd.conf config file.
    #

    authoritative;

    subnet 192.168.0.0 netmask 255.255.255.0 {
    # interface eth0;
    range 192.168.0.20 192.168.0.250;
    #range 192.168.1.150 192.168.1.200;

    default-lease-time 600;
    max-lease-time 7200;

    option domain-name “example.com”;
    option domain-name-servers 192.168.0.1;
    option broadcast-address 192.168.0.255;
    option routers 192.168.0.1;

    # option ip-forwarding off;

    #next-server 192.168.0.1;
    #get-lease-hostnames true;

    option subnet-mask 255.255.255.0;

    # option ntp-servers 192.168.1.100;

    option root-path “/opt/ltsp/i386”;
    if substring( option vendor-class-identifier, 0, 9 ) = “PXEClient” {
    filename “/ltsp/i386/pxelinux.0”;
    } else {
    filename “/ltsp/i386/nbi.img”;
    }
    }

    =============EOF===========

    To solve this problem what should i do? Please suggest me,i am waiting for your reply
    With regards,
    Abdul Wahid

  2. zigurds says:

    Hi,
    Your dhcp.conf file look like straight from installation and you have not done any changes to it. So to try to help you fix this I need to know your network setup in which you are trying to make this system work. Is your LTSP server machine connected to router, does it have static IP, where in your network is LTSP client that wants to connect to server. Then we can try to figure out what’s wrong. It looks like that your network address my be defined not properly and your LTSP client does not see the DHCP server.
    Try to restart DHCP server “sudo /etc/init.d/dhcp3-server restart” and see if it works. Then we need to look at your network setup.

    Error code PXE-E51 relates to this problem: No DHCP or proxyDHCP offers were received. The client did not receive any valid DHCP, BOOTP or proxyDHCP offers. IP from DHCP so you can try to check each of the following network configuration items:
    • DHCP services are not available on the network to which the PXE-enabled NIC is connected.
    • A DHCP proxy or IP helper address is not configured for the subnet on which the PXE client is connected.
    • The switch port connected to the PXE NIC is running Spanning Tree Protocol, EtherChannel Protocol, or Port Aggregation Protocol and is thus not activated immediately when a link is detected. This forces the DHCP request from the PXE client to timeout.
    • DHCP is available on the network, but PXE is not.
    • The network cable is not attached to the PXE-enabled NIC on the target server.

    Zigurds

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s