Installing LTSP in Debian 4.0: LTSP 5 or LTSP 4.2?

[castaway]

Since posting this review of LTSP 4.2 and LTSP 5, I have continued to experiment with LTSP 5. I have finally found how to successfully install LTSP 5 with etherboot floppy workstations on my LTSP network containing RealTek-8139 etherboot floppy workstations. Detailed instructions are posted in this forum:

http://www.linuxagora.com/vbforum/showthread.php?t=860

Edit 24 September 2007
Castaway

Installing LTSP in Debian 4.0: Which version--LTSP 5 or LTSP 4.2?

INTRODUCTION

Several years ago I decided to use the "thinclient" approach and network all the computers in my home. Because of problematic lan chips on my motherboards I spent a great deal of time getting LTSP to work. After replacing them with network cards I succeeded in successfully installing LTSP W4.1 in Libranet 2.81. Because I had been unable to find a detailed howto for installing LTSP, I decided to write one for newbies like me. When Debian 3.0 was introduced, my howto was modified, first for Sarge and later for testing Etch.

Debian has just released 4.0 Etch which offers two versions of LTSP: LTSP 5 and LTSP 4.2. I have tested both versions of LTSP using the Debian "base" installation with icewm added, and the "desktop" installation with Gnome.

LTSP 5

LTSP 5 is so new that there is little information on how to install it. There is no manual available for it on the LTSP.org website. The rare web references regarding its installation are scarce in details. I am beginning to wonder if anyone has successfully installed LTSP 5 in a "working" environment.

The problems I encountered while installing LTSP 5 are as follows:

1) If atftpd has already been installed, it must be removed before installing LTSP 5. Atftpd's working directory is /tftpboot, a root directory. This location is no longer recognized in version 5 of LTSP. If you try to remove atftpd after LTSP 5 has been installed, the removal gives numerous error messages and leaves many of the program files and directories behind.

2) Although LTSP 5 installs tftpd-hpa, tftpd-hpa is not properly configured to work with LTSP. The working directory for this tftp version is also /tftpboot, the directory buried deeply beneath the /var root directory. However, this directory location is recognized by LTSP 5. Tftpd-hpa is configured on installation to run on "demand". It did not run at all. When I finally enabled error logging by adding the "-l" attribute (lowercase L) to its configuration file /etc/inetd.conf, I found that another program was using the tftp port: tftpd-hpa could not load. I modified /etc/default/tftpd-hpa so that tftpd-hpa would run as a daemon. This solved the problem.

3) Dhcpd.conf must be revised before it will work -- but only after you find the location of the sample file, installed by LTSP in the /usr/share/doc/ltsp-server/examples directory. (In previous versions of LTSP the sample version of dhcpd.conf was installed in the /etc/dhcp3 directory, available for immediate use.)

As was the case with previous versions, the sample dhcpd.conf file has your computer's IP address entered correctly in some areas of the file; other areas contain only non-working generic IP addresses that you must change. If you know nothing about dhcpd.conf files, you will probably not recognize all the IP addresses that need to be altered, nor which IP address from your network to use.

A copy of dhcpd.conf from your previous LTSP installation will NOT work. The location of the tftpboot directory has changed with LTSP 5. Names of the kernel images are also different.

Despite the fact that LTSP 5 installs a revised version of dhcp3-server, the sample dhcpd.conf file does not contain the necessary option "next-server xxx.xxx.xxx.xxx" that this version of the dhcp3-server requires. Without the next-server IP address your workstation will run in circles, unable to connect to the server.

Getting dhcpd.conf to work has always been the most difficult part of setting up LTSP.

4) The types of linux kernels used with LTSP 5 are different from those in earlier versions. If you previously used a .com boot image with LTSP 4.1 in order to boot from your workstation's hard drive, the workstation will no longer boot. The new kernel image no longer recognizes (DOS) .com boot images.

5) You must use an /opt/ltsp/i386/etc/lts.conf file. LTSP provides a sample copy, well hidden, as /opt/ltsp/i386/usr/share/doc/ltsp-client/examples/lts.conf. The file must be modified before use. After a while I gave up and used my LTSP 4.1 version of lts.conf. The 4.1 version requires one modification before use: change the stanza "SCREEN_01 = startx" to "SCREEN_07 = startx".

6) Even if your workstation is eventually able to connect to the server, you will find the screen resolution is only 640x480. (I haven't seen a resolution this low since the late '80s.) Meanwhile your workstation screen is displaying a notice that you will connect at 1024x768! I tweaked some of the xorg files and the lts.conf file, but without success.

7) Once you are able to successfully connect to your server, your workstation will connect only intermittently -- or never again. Generally the 2nd or 3rd time the workstation boots it will be unsuccessful in completing a connection with the server. The workstation will hang, dispensing a "cannot find file" error. This happens even if you have NOT altered any files since your first successful connection. LTSP's maintainer published a fix for this problem a month ago on one of the bulletin boards. The fix is already incorporated into the Debian dhcpd.conf file. Alas, the fix does not work. I have fiddled with dhclient files, resolv.conf files, log files, debug programs, interface files, etc., all without avail. The error message suggests that the error is a result of NFS timing-out because it has lost the location of the kernel file that is to be copied to the workstation. And you will notice from the error message that the router's IP address has now been substituted for the LTSP server's IP address. These data suggest to me that a file on the server has been automatically updated -- incorrectly -- by LTSP.

In summary, although LTSP 5 is included in Etch, installation bugs prove it is still unstable experimental software. LTSP 5 is best left for expert use.

LTSP 4.2

LTSP 4.2 is also available from the Debian 4.0 Etch repositories. I highly recommend it. You can install it in about 20 minutes -- not including the time spent downloading the LTSP components, trying out various romomatic.org roms for your workstations, or reading my extensive howto. Find my installation directions for Sarge & testing Etch at:

http://wiki.ltsp.org/twiki/bin/view/Ltsp/Debian

Be sure to follow the alternate Etch directions given in the curly brackets {}. Installation of LTSP 4.2 is virtually the same for both testing Etch and the new stable Etch.

The problems I encountered while installing LTSP 4.2 are as follows:

1) The /etc/dhcp3/dhcpd.conf file must be revised before use. The sample LTSP configuration file suffers from the same incomplete installation of user data as does LTSP 5. Use my howto's dynamic workstation version of dhcpd.conf to overcome this problem. Be sure to make the following modifications to the howto version before using it:

__1) Unremark the "next-server" stanza at the top of the file. Replace the IP address with that of your own LTSP server.

__2) At the bottom of the file, modify the filename of the kernel image to be uploaded to the workstation. LTSP 4.2 uses a different version. Go to the directory:

/var/lib/tftpboot/ltsp/i386/

and copy down the correct name for the file. Then enter it into dhcpd.conf. Do not change the path of the file -- change only the filename. (Note that if you try instead to use the sample dhcpd.conf file installed by LTSP 4.2, the file name for the kernel image is incorrect in it also.)

2) There are NO other problems!

HINTS FOR THOSE SETTING UP AN LTSP 4.2 WORKSTATION

In the section of my howto for setting up a floppy disk workstation, use a Thinclient multi-rom floppy boot disk image instead of obtaining a single rom floppy image from romomatic.org. The Thinclient version contains numerous roms representative of the more common network cards. During the boot process it will sequentially try each of the contained images. This disk may save you much time as opposed to trying romomatic.org's numerous individual rom images one-by-one. The multi-rom disk image can be found at:

http://sourceforge.net/project/showf...group_id=80408

At the bottom of the page find "thinstation contrib" > "Universal network boot floppy/cd/hd" > "BootDisk522b.zip." This is the version I used. The version "network_boot_floppy+cd+hd_540.zip" supposedly contains more recent nic rom images.

However, if you have one of the new "designer" motherboards with their highly proprietary network chips, romomatic.org may not yet have a rom image. In such instances, it is probably better to turn on PXE booting in your computer's bios and use the motherboard's builtin lan and PXE boot rom for your LTSP workstation. Because having to change the computer's bios everytime you want to use it for another task is inconvenient, PXE booting is best reserved for a computer which will be used solely as a workstation.

Edit 9 June 2007: Name of multi-rom image corrected.

[castaway]

Further Notes: How to Install LTSP 5 in Debian 4.0

With continued experimentation after submitting the above post, I have discovered it is actually possible to successfully install LTSP 5 in Debian if you use the Debian derivitive Edubuntu 7.04 and not Debian 4.0 itself.

How to Succesfully Install LTSP 5 in Edubuntu 7.04

The most recent version of Edubuntu features a suprisingly easy installation procedure for LTSP 5 consisting of only five steps:

1) Install Edubuntu. (Be sure to setup a static IP address!)

2) Immediately choose to install LTSP 5 at the conclusion of Step #1. The computer will then reboot.

3) Revise /etc/ltsp/dhcpd.conf by replacing all IP addresses with those of your own network.

4) Restart the dhcp deamon -- "/etc/init.d/dhcp3-server restart."

5) Setup your workstation:

__1) Floppy-disk booting method if using an older computer/motherboard --

Obtain the multi-rom boot image "BootDisk522b.zip," usable with more than 30 nic's:

http://sourceforge.net/project/showf...group_id=80408

You will find it at the bottom of the page under the cagegory "thinstation contrib" > "Universal network boot floppy/cd/hd." (The version "network_boot_floppy+cd+hd_540.zip" supposedly contains more recent nic rom images.) Download the image and transfer it to a floppy disk with the "cat" command if using linux, or "rawrite" if using Windows. (Directions are in the accompanying ReadMe.txt.)

__2) PXE-booting bios method if using a newer computer/motherboard --

Modify your workstation's bios (during bootup) so that it will boot from a network. Also enable PXE booting.

6) Boot your workstation. That's it! You are finished.

(An Edubuntu warning: Firefox has a tendency to crash if the screensaver starts while Firefox is running!)

How to Fail at Installing LTSP 5 in Edubuntu 7.04

If you do not install LTSP 5 at the same time you are installing Edubuntu from the cd-rom, but download LTSP 5 later from the Ubuntu repositories, you will not be able to successfully install LTSP. You will experience the same problem of incorrect updating of the LTSP files described in my earlier posting regarding Debian 4.0 Etch (see above). However, your workstation will display the LTSP desktop at a usable resolution, not 640x480.

LTSP 5 Cannot be Installed in any Debian 4.0 Distribution

I had the same problems while installing LTSP 5 with both Lenny and Sid as I did with Etch. I was unable to install a workable version of LTSP 5 in Debian 4.0.

Conclusions

1) If you must use LTSP 5 because you have a newer graphics card or for some other reason, then obtain Edubuntu 7.04 and install LTSP 5 from the cd-rom at the same time you install Edubuntu -- not later.

2) LTSP 5, as found in the Debian and Ubuntu repositories is essentially "broken" until its maintainers reveal the secrets for its successful installation.

[fos]

Another great HOWTO. Thank you!