Category Archives: LTSP

Linux Terminal Server Project, make a Linux desktop a terminal server than can be used by network booted thin clients.

Introducing the WebLive API

Posted on 2011/03/06 by Stéphane Graber

After working on it for the last two weeks, I’m proud to finally announce the WebLive API.
As a reminder, WebLive is the name used for the daemon, Drupal plugin and scripts used to run http://www.edubuntu.org/weblive
Since last week, all the code is now available here: https://launchpad.net/weblive

The API is exported over JSON and example code is available in the branch called ltsp-cluster-agent-vmmanager in the client directory. When interfacing with python, it’s recommended to use the “weblive.py” module as it’ll be updated should the JSON API change or be extended in the near future.

Exported functions are:

  • create_user(serverid, username, fullname, password, session)
  • list_everything()
  • list_locales(serverid)
  • list_packages(serverid)
  • list_servers()

The following functions are exported over authenticated XML-RPC (for management):

  • delete_user(serverid, username)
  • set_disabled(serverid,status)
  • list_users(serverid,all=False)

The main weblive instance is available at https://weblive.stgraber.org/weblive/json and is the one used by Edubuntu.

The drupal-weblive branch contains the Drupal module which is now just a client to the JSON API.

The first use of that API after the Drupal module is Natty’s software-center which since last week ships with code to connect to WebLive.
If you use up to date Natty, you’ll need to install “qtnx” from universe and then start: software-center –with-weblive

All the packages available in WebLive will then have a “Test drive” button you can click to test that app remotely from a WebLive server.

WebLive integration in software-center

The software-center integration is experimental and will hopefully be improved by the time Natty is released. As Ubuntu doesn’t ship qtnx by default, WebLive won’t be visible in the default Ubuntu install, though it’ll be for Edubuntu.

Note: It can take up to a minute to connect to a server. There’s currently no user feedback during the connection process unless you watch the terminal from which you started the software center.

The current code requires your username and hostname to be ascii lowercase alpha characters only. I posted instructions as a comment to get the development branch that doesn’t have this restriction.

Posted in Edubuntu, LTSP, Planet Revolution-Linux, Planet Ubuntu, WebLive | Tagged | 11 Comments

Getting ready for IPV6

Posted on 2010/12/31 by Stéphane Graber

I’ve been regularly playing with IPV6 since mid-2006 when I first opened an account at SixXS ang got my first IPV6 tunnel up and running. Sadly at that point, there wasn’t much Point of Presence for tunnels, not even mentioning the state of native IPV6 networks…

Relatively recently my dedicated server provider started offering native IPV6 connectivity in their Nuremberg-based datacenter. They offer a /64 per server which should be plenty enough for most users and allows for stateless configuration of a single network. Unfortunately in my case, I’m running OpenVZ, LXC and KVM on that box, meaning multiple distinct networks with bridging and firewalls.

As I also wanted IPV6 connectivity for my home network and would rather have a single provider for both, I started looking at the current state of tunnel brokers to end up choosing Hurricane Electric who offer free IPV6 tunnels and one /48 network per subnet which is exactly what I needed. They have Point of Presence pretty much all around the world which means very low latency IPV6 for all my networks.
They also happen to be one of the two upstream providers of the ISP we use at the office.

So I started configuring my Vyatta (Debian-based router distribution) routers to handle the IPV6 tunnel, send Router Advertisement to all my networks (radvd), relay DHCPv6 to my DHCP server and firewall incoming traffic.
That was surprisingly easy, taking only a few minutes, copy/pasting the configuration provided by the tunnel broker and setting up the firewall rules.

I then made sure all my main services are working properly with IPV6, for now that includes, DNS servers, Web servers, Mail servers and shell access. Backported Natty’s isc-dhcp-server to 10.04 LTS and moved my DHCP to using it and created a minimal configuration to get stateless DHCPv6 to announce my NTP and DNS servers.
I also updated my public DNS to include AAAA records for all services that have dual-stack support and got my registar to add IPV6 glue records to my domain.

I’ve now been running that setup for a week or so for my home network, dedicated server and office network. Running wireshark for a few hours showed that almost half of my connections are IPV6 (mostly on my own networks).

I’ve been surprised to see how well Ubuntu Natty’s NetworkManager copes with IPV6 network. In my case, it successfully noticed the “other-config” flag in the router advertisement and started dhclient to grab the DNS and NTP configuration from the DHCPv6 server.

So I now have a working environment to developer the next generation LTSP-Cluster which is supposed to have complete IPV6 support from the first release.

Let’s hope we’ll see more IPV6 deployment in 2011.
Happy new year everyone !

Posted in LTSP, LXC, Planet Revolution-Linux, Planet Ubuntu | Tagged | Leave a comment

Want your own Edubuntu weblive ?

Posted on 2010/12/08 by Stéphane Graber

Since I announced Edubuntu WebLive 8000 users have been testing Edubuntu using it.

Edubuntu WebLive

After a bit of cleaning up and packaging, I’m now pleased to announce that the source code for both our Drupal plugin and the XML-RPC daemon is available on Launchpad: https://code.launchpad.net/vmmanager.

Drupal plugin

Features:

  • Provider the user interface for Weblive, like the one on: http://www.edubuntu.org/vmmanager
  • Gives a basic administration interface to enable/disable the NX servers and update all the text shown in the user interface
  • Code is PHP using the Drupal form APIs and php-xmlrpc to contact the ltsp-cluster-agent plugin

Installation is relatively trivial, just follow the README file in the branch.

ltsp-cluster-agent plugin

Features:

  • XML-RPC service (authenticated and using HTTPS) that Drupal uses to create new users
  • Database of all accounts ever created, their status and expiry time
  • Support for multiple SSH servers
  • Client to query the database (also over xml-rpc) to gather statistics or manually create/remove accounts
  • Code is python, using paramiko for SSH and storm+sqlite as ORM

Installation is straightforward as everything is packaged here: https://launchpad.net/~stgraber/+archive/experimental

ltsp-cluster-agent is a python daemon designed for use by LTSP and LTSP-Cluster. More on that in a later post.

The VM itself

For Edubuntu, our VMs are entirely automatically generated using debian-installer preseeding and KVM.
Unfortunately these scripts are not clean enough yet for me to release them, I’d expect to have them out very soon though.

The basic requirement for the VM is to have these packages installed:

  • ltsp-cluster-accountmanager (used to cleanup session leftovers)
  • freenx-server (the NX server)

We have recent versions of both in Revolution Linux‘s PPA. ltsp-cluster-accountmanager is also in the archive since karmic and I’m hoping for freenx-server to enter the archive soon.

I’d also recommend removing the following packages as they caused some issues with Edubuntu WebLive:

  • network-manager, network-manager-gnome, network-manager-pptp, network-manager-pptp-gnome
  • jockey-common, jockey-gtk
  • rtkit

As usual, comments, patches and bug reports are welcome. I’d also be happy to hear from other deployments of WebLive !

Posted in Edubuntu, LTSP, Planet Revolution-Linux, Planet Ubuntu | Tagged , | 3 Comments

Announcing LDM 2.2 and LTSP 5.2.5

Posted on 2010/12/06 by Stéphane Graber

Today, I’m pleased to announce the release of both LTSP 5.2.5 and LDM 2.2.

Quite a lot of changes went in over the past few months, 25 commits since the last ltsp release and 82 for ldm.
Here’s a quick overview of what’s new.

Big LDM refactoring and cleanup

Almost a year ago, my company got some funding from the NLNet foundation to work on a few LTSP and LTSP-Cluster related projects. One of them was to make LDM extensible, moving it to a plugin infrastructure and making it’s interface a bit more flexible.

I’m glad to announce that all of that work landed upstream almost two months ago and since then has been cleaned up and tested.
From a user experience point of view, the only noticeable change should be that the same login screen can now be used for Linux (ssh), Windows (rdp) login and for fat clients.

From a sysadmin/developer point of view, a lot changed:

  • Support for multiple backends. The old SSH backend as been ported to the plugin infrastructure and an RDP plugin has been written. A pam/libssh plugin should soon replace the current SSH plugin
  • Switched to using multiple windows and a window manager instead of our old fullscreen window. It should make it a lot easier to add more widgets to the login screen.
  • New logging functions with different logging levels and standardized logging output with syslog support

LDM 2.2

Remote apps support

It’s now been a few years since we have local applications supported in LTSP. It’s greatly improved over the years to get to what we currently have in LTSP.
The biggest issue of it was that if you start a software like firefox as a localapp and click on a .pdf/.odt/… document in it, it won’t be able to open them unless the required viewer is also a localapp.

That’s now been fixed thanks to the work done by Marc Gariépy and Gideon Romm during the last LTSP hackfest in Southwest Harbor, ME.
ltsp-remoteapps is a new command that can be assigned to mimetypes on the thin client and will open the viewer on the application server.

For the user, this means that if they click on a .odt document in their local firefox, it’ll now automatically open it in OpenOffice Writer on the application server.
Giving the desktop-like experience that was missing for local applications.

Other than these two big changes, we had our usual set of bug fixes, cleanup and translation updates.

Packages for Ubuntu Natty are already available and a backport for Ubuntu 10.10 (Maverick) is available in my PPA: https://launchpad.net/~stgraber/+archive/ppa

Posted in LTSP, Planet Revolution-Linux, Planet Ubuntu | 3 Comments

LTSP 5.2 is out !

Posted on 2010/02/21 by Stéphane Graber

After almost two years or work and 994 commits later made by only 14 contributors, I’m proud to announce that the Linux Terminal Server Project project released LTSP 5.2 on Wednesday the 17th of February.

LTSP 5.2 is released

As we wanted this release to be some kind of a reference point in LTSP’s history, we also released LDM (LTSP Display Manager) 2.1 and LTSPfs 0.6 on the same day.

Packages for LTSP 5.2, LDM 2.1 and LTSPfs 0.6 are already in Ubuntu Lucid and a backport for Karmic is available in my PPA.
For other distributions, I’m expecting packages to be available very soon. If you want to check out the code, it’s on Launchpad.

It would take a lot of pages to describe all that was changed during these two years so I won’t even try to do that :)

Instead, I’ll simply give you a short overview of what one can do with LTSP nowadays:

  • Boot a Debian/Fedora/Gentoo/Ubuntu environment using PXE (dhcp + tftp) and connect to an application server using SSH and X11.
  • Either run the whole session remotely or run select applications locally to use specific hardware or advance 3D capabilities
  • If running Ubuntu, run everything locally and only select applications remotely (that’s called Fat Client)
  • Support for RDP sessions using rdesktop
  • Working local block devices like harddisks, floppy disks and cd-rom drives (thanks to ltspfs)
  • Easily extensible thanks to an amazing plugin infrastructure, providing hooks pretty much everywhere
  • Multi-lingual support in LDM and most of our scripts
  • Scalable to thousands of thin clients, at least on Ubuntu, thanks to LTSP-Cluster
  • Complete documentation, in the LTSP handbook
  • Active and supporting community, mostly on the various mailing-lists and #ltsp (freenode)

Now, to quickly summarize what changed between 5.1.99 and 5.2, here’s the changelog I used in the Ubuntu package:

  • Improve fat client support (a lot faster)
  • Update nbd-proxy for stability
  • Rewrite of ltsp-update-image
  • Updated sound configuration
  • Lots of optimizations
  • Added ssh and whiptail screen script

LDM was made a bit faster in 2.1 and a few ltspfs bugs have been fixed as well as lot of optimization and code cleanup (in both cdpinger and ltspfsd).

Measure boot time on Ubuntu Lucid is under 10s on an Atom-based thin client (1.6Ghz, Hyper-Threated with 512MB of DDR2). That’s just blazing fast !!

Once again, thanks to everyone who made that possible. I’m really impressed by all the changes made to LTSP over the past few years and I really love being a part of it.

No releases are perfect, so if you find bugs, please report them here (for LTSP), here (for LTSP in Ubuntu) or here (for LTSP-Cluster).

Posted in LTSP, Planet Revolution-Linux, Planet Ubuntu | 27 Comments