Edubuntu : LTSP, résolution de problèmes

Page en cours de construction : en attendant, vous pouvez consulter les "FAQ" ici (en anglais) :

Cette page regroupe un ensemble d'information pour résoudre les problèmes classiques de configurations ou d'utilisation

• La liste de diffusion des utilisateurs francophones d'Edubuntu

https://eshu.ubuntu-eu.org/mailman/listinfo/edubuntu-fr

• La liste de diffusion des utilisateurs anglophones d'Edubuntu:

https://lists.ubuntu.com/mailman/listinfo/edubuntu-users

Cela arrive généralement quand l'adresse IP du serveur n'est plus la même, car la connexion entre serveur et client se fait via SSH donc les clés de cryptages sont générées en fonction des adresses IP. Pour résoudre ce problème, tapez dans une console sur le serveur:

sudo ltsp-update-sshkeys

• The Edubuntu Handbook – http://doc.ubuntu.com/edubuntu/handbook/C/
• The Ubuntu LTSP Wiki https://help.ubuntu.com/community/UbuntuLTSP
• The LTSP Manual – http://wiki.ltsp.org/twiki/bin/view/Ltsp/Documentation
• The Gentoo LTSP Guide – http://www.gentoo.org/doc/en/ltsp.xml
• Le site Edubuntu francophone – http://www.edubuntu-fr.org

Cette question est examinée dans le détail sur cette page:
https://help.ubuntu.com/community/EdubuntuDocumentation/EdubuntuCookbook/HardwareRequirements

Oui, dans le menu Système ⇒ Administration, sélectionnez Thin Client Manager.

Oui, vous devez construire un environnement LTSP séparé sur le serveur comme suit:

sudo ltsp-build-client --kiosk --base /opt/ltsp-kiosk/

Et configurer le serveur DHCP (/etc/ltsp/dhcpd.conf) pour que les clients concernés utilisent le kiosque Web:

option root-path="/opt/ltsp-kiosk/

The login screen on thin clients is generated by ldm running on the thin client. You can modify this, in the ltsp chroot environment themes} by taking a copy of the theme, making your copy the default and modifying the artwork default}

Now just modify the images in mytheme}

This was a known issue for a long time with the closed source adobe flash plugin. It has recently been fixed, although the fix did not make it into Edubuntu feisty. The simplest fix is to download and install the libflashsupport package on your server with these commands: libflashsupport_1.0_2219-1_i386.deb_sudo_dpkg_-i_libflashsupport_1.0_2219-1_i386.deb} For more info on the fix and the work done, you can look here:

• http://pulseaudio.revolutionlinux.com/PulseAudio

A short overview about how thin clients boot: 1. thin client starts and sends a PXE or Etherboot request to the network 1. DHCP server answers and tells the client where to get the kernel and the system from 1. client pulls kernel via TFTP and mounts the filesystem via NFS from the server

WLAN cards don't support PXE or Etherboot, so there is no way for the thin client to send a PCE or Etherboot request to the network with a wireless card. The only way to achieve this would be to have the kernel and initramfs stored locally somehow (which indeed is not a LTSP setup anymore but rather a minimal local boot that mounts its filesystem via NFS). Additionally you would need to handle the ESSID for the WLAN as well as potential encryption via bootoptions.

It is not impossible to build a locally booting WLAN image, but you will always need local media (usb-stick, flashcard or CD) to boot from and it is far from being supported by us (implementing it will take some time and testing).

This was a problem up to and including Edubuntu Feisty. They are old, temporary "swap" files from thin clients which were not shutdown properly. Adding the following line to /etc/hosts.allow:

nbdswapd: ALL: keepalive

should stop newly created files getting left around. You may find it easiest to reboot to clear the existing ones though.

In order to debug individual thin clients it can be useful to be able to login in a text session on the thin client. To do this: 1. Login as normal and start a terminal (under applications→accessories menu). 1. Type i386} and press return. You will be prompted for your password. 1. At the next prompt, type passwd} and press return. You will be prompted for the root password for the thin clients. 1. If you're running gutsy (v7.10) or newer, you must now run sudo_ltsp-update-image} and reboot the thin client you wish to login to.

Having done the above, you can go to any of your thin clients, hold <ctrl><alt> and press F1. You should now be able to login with the username root and the password you set.

There isn't currently a way within the standard system "users and groups" manager tool. However, several ways exist which were mentioned in this thread on edubuntu-users mailing list.

https://lists.ubuntu.com/archives/edubuntu-users/2007-January/thread.html#529

most of the ideas centre around the createusers} script which is part of Matt Oquist's smbldap setup script.

http://www.majen.net/smbldap/

One of the most common reasons for USB storage devices not to work is the user needs to be in the fuse} group. By running the groups} command a user can check what groups he is in. You can change user groups in the user admin tool which you use to create users.

If that isn't the answer, there are instructions for debugging local devices here:

* https://wiki.ubuntu.com/DebugLocalDev