The future of the Linux Terminal Server Project (Linux.com)

[Posted September 22, 2006 by ris]

Linux.com covers a recent meeting to discuss the Linux Terminal Server Project. "Distributed development makes open source tick, but sometimes you just have to get people together in a room -- which is what the Linux Terminal Server Project did last weekend. Members of the project, and developers for several distributions, gathered in Clarkston, Michigan last weekend to plot the future of LTSP -- and it looks good."

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The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 23, 2006 17:45 UTC (Sat) by elicriffield (guest, #33738) [Link] (15 responses)

It annoys me when i have to dig and dig to figure out what a product actually does.

LTSP says its: "LTSP is an add-on package for Linux that allows you to connect lots of low-powered thin client terminals to a Linux server. Applications typically run on the server and accept input and display their output on the thin client display"

How is that diffrent from X windows? I know what X windows does what does LTSP do?

I'm sure it describes what it does somewhere, but you'd think it would be in the description. More and more i see descriptions that don't want to get to technical so there so vague there useless.

Eli

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 23, 2006 19:06 UTC (Sat) by arcticwolf (guest, #8341) [Link] (1 responses)

According to Wikipedia, LTSP actually uses X at its core, but builds a more complete, "turn-key" environment on top of it - kind of like the difference between the Linux kernel and a distro, I assume.

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 23, 2006 22:55 UTC (Sat) by mrons (subscriber, #1751) [Link]

I've been using LTSP since it began, and my own home grown version before that.

Essentually, you take a low powered workstation and make it boot a linux kernel over the net. The kernel will have an NFS root and /usr filesystem and (optionally) network swap.

You then fire up an Xserver on the workstation and point it at a remote display manager (xdm,gdm,kdm) which will give you a login screen. Users login to this system and run their applications there, remotely displaying back to their workstation.

LTSP installs on an existing linux/Unix box and provides, to the workstations, an NFS root and /usr filesystems, a linux kernel and initrd, various X servers, and various tools for managing multiple workstations. There are also several enhancements to take advantage of any "local devices" the workstation may have.

So LTSP is an implementation, and enhancement, of the old idea of an X Terminal. It is also built with Free software.

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 23, 2006 22:46 UTC (Sat) by penguin (guest, #36771) [Link] (12 responses)

Ltsp is a complete package for running thin clients that boot over PXE. It bootstraps a kernel over tftp, mounts nfs and slaps open an X session to the xDM on the server. It also consists of daemons that handles local device support. Like plugging in a usb thumbdrive puts it on your desktop. LDM is another fun thing to use in conjunction. Its and xdm that does ssh tunneling, talk about secure clients =)

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 24, 2006 12:00 UTC (Sun) by drag (guest, #31333) [Link] (11 responses)

Ya that's the jist of what I understand.

It's nothing you couldn't do yourself using a bunch of different software packages and manually setting everything up. It's just their to make it easier and take care of details and such that you may not notice at first.

Sort of like the difference between Ubuntu vs Linux from scratch. (although obviously to a different scale.)

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 24, 2006 21:29 UTC (Sun) by job (guest, #670) [Link] (10 responses)

So it's a Linux distribution?

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 25, 2006 7:04 UTC (Mon) by drag (guest, #31333) [Link]

Sort of, I guess. But not realy. Keep in mind that I haven't used it myself.

You need two parts..
The boot/application server. Were the 'X clients' reside and user management is done and stuff like that.
The mini-linux system for booting and running the X server on the diskless clients.

So it's more like a system for doing X terminals were your using a existing Linux distro to do the X clients (the applications) portions and to serve as a PXE (or etherboot or whatnot) boot strap server to launch a mini linux system for running the diskless X terminals.

Before I think they used a stripped down redhat system for running the diskless clients.. but it makes sense that if your using Debian (for instance) to run LTSP from you'd want to use a stripped down version of that system for running your clients. Same package versions, updates and drivers and that sort of thing. Which is the direction things seem to be going.

It's nothing you can't do yourself, of course, by taking a Debian or Redhat or whatever box and setting up client images and configuring your graphical login manager and stuff. LTSP would just aim at making it much easier to setup and manage.

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 25, 2006 14:20 UTC (Mon) by elicriffield (guest, #33738) [Link] (5 responses)

All the other comments prove my point. Lots of smart (all lwn.net readers are smart, right?) people can't tell what it is without a lot of digging.

Why can't LTSP say in there discretion "LTSP is a configuration tool to make setting up diskless remote X displays easier"

Then i would know what it does. From its description it makes it sound like before LTSP there was no such thing as thin clients on unix. Anyone who who's seen 15 year old X terminals would disagree.

Are they trying to take credit for something they didn't do?

It's things like this that someone sells to management for some insane amount of money and then it gets handed down to a real Linux admin with something like "Here this product only cost us 10x your salary this year and it allows you to remotely login to a Linux box"

Not that LTSP is selling anything but they have the same kind of vague description and overselling of what the product does I've seen from commercial products.

Eli

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 25, 2006 16:25 UTC (Mon) by hathawsh (guest, #11289) [Link] (4 responses)

"Are they trying to take credit for something they didn't do?"

No. The linux.com article links to a history page on ltsp.org that says:

"... the credit belongs to many people who's names are not mentioned in this document. The developers of Linux, The X Window System, Etherboot and the thousands of lines of code that glue this technology together are the people who we are gratefully indebted."

Also, the project describes itself without any boasting at all:

"LTSP is an add-on package for Linux that allows you to connect lots of low-powered thin client terminals to a Linux server. Applications typically run on the server, and accept input and display their output on the thin client display."

It doesn't say "LTSP is the only way", "LTSP is the market leader", or any of the other wasteful things that commercial projects say. Like most open successful source projects, LTSP relies on honesty and a good reputation to get the message out, not noise. So your concern that LTSP is taking undue credit is quite unfounded.

What LTSP produces is more than just a configuration tool. There's interesting, original software going in there somewhere. For example, when today's users plug in a USB memory stick, they expect the computer to pop open a window showing the memory contents. That is a reasonable expectation that shouldn't be broken even if you're running a thin client, yet it is not obvious how a thin client should fulfill that expectation. Well, LTSP has apparently solved that problem, among many others, I'm sure.

The LTSP home page says, at the bottom, "The LTSP project contains all of the information and software you will need to build your own diskless workstations and configure your server." That description is spot-on, I think. Perhaps it should be at the top rather than the bottom; that would be a reasonable request.

(BTW, I'm not affiliated with LTSP.)

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 25, 2006 16:28 UTC (Mon) by hathawsh (guest, #11289) [Link]

s/open successful source projects/successful open source projects/

;-)

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 25, 2006 20:03 UTC (Mon) by elicriffield (guest, #33738) [Link] (2 responses)

If it does more then config other services then i still don't know what it does.

Eli

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 26, 2006 0:43 UTC (Tue) by wookey (guest, #5501) [Link]

I used LTSP on a project a couple of years ago, and even used it on a couple of client machine on the local net for a while, so I have a reasonable idea of how it works. The LTSP package installs (or did then) a complete root environment for the clients to mount as well as config files you could tweak from which the client-machine config files were generated dynamically at boot-time. That is rather more than just 'a config system for existing software'. It is, as people have said, sort-of a mini linux distro as well as a remote services config tool. And then there are the daemons to prove sound and other 'multimedia', printing, and USB accesss on the client machines, and etherboot ROM/floppy/HD/CD generation so if your machine is too old to PXE boot it can still network boot.

In many ways it is 'just' some config of existing tech, but the sum really is much greater than any of the individual parts - it is really quite powerful. I did have problems in practice with a slow network and the load it places on the server machine so it does have its limitations. It worked great for the entirely-volatile embedded system we did with it though.

The future of the Linux Terminal Server Project (Linux.com)

Posted Sep 26, 2006 15:44 UTC (Tue) by sbalneav (guest, #12434) [Link]

If one goes to the LTSP.org site, and clicks on "Documentation", you'll find some very complete documentation, including a very comprehensive "Theory of operation" section, which describes exactly what's going on.

Scott Balneaves
sbalneav@ltsp.org

So it's a Linux distribution?

Posted Sep 26, 2006 1:47 UTC (Tue) by kmself (guest, #11565) [Link] (2 responses)

Pretty much.

That's its strength and weakness.

The good side is that all you need is to install LTSP and you're set. The downside is that if you're used to running another distro; using that distro's update tools; and accessing its bugfix, documentation, and support infrastructure, LTSP leaves you somewhat out in the cold.

There are no technical reasons why LTSP couldn't simply be an add-on package to any standard APT or RPM-based distro, but it's not. There are equivalent tools for Debian, FC, etc., but they don't have the mindshare of LTSP. I'd much prefer that projects pulled together rather than apart.

So it's a Linux distribution?

Posted Sep 26, 2006 15:49 UTC (Tue) by sbalneav (guest, #12434) [Link] (1 responses)

> There are no technical reasons why LTSP couldn't simply be an add-on
> package to any standard APT or RPM-based distro, but it's not.

That was entirely the point of the hackfest. On Debian, Ubuntu, and soon to be Fedora, the LTSP chroot will be built using the local package management tools, and packages.

We look forward to working with Novell, Mandriva, Slack, Gentoo, et. al. in the future to help them to fit into this model as well.

Scott Balneaves
sbalneav@ltsp.org

So it's a Linux distribution?

Posted Sep 26, 2006 16:55 UTC (Tue) by dberkholz (guest, #23346) [Link]

I'd certainly like to help get Gentoo working properly with this. Where do I sign up?

Good!

Posted Sep 27, 2006 7:10 UTC (Wed) by ncm (guest, #165) [Link] (2 responses)

This is actually pretty exciting. Expect, in a few months, to be able to say something like "apt-get install ltsp", and have a working service all ready to connect an unlimited number of thin clients to. This makes it very easy to upgrade, e.g., a library or school PC lab room from WinXX to Linux, in-place, just by putting Debian (or something) on the file server and changing a single BIOS option on each workstation.

Yes, as it is you could put old-style LTSP on the file server, but then you have to administer an LTSP system, which has much less community support than your (otherwise favorite) Linux distribution. This new mode allows the LTSP team to concentrate all their efforts on the core project, and drop the distracting responsibilities of maintaining a whole distro, something they don't really have the resources to do well anyway.

Good!

Posted Sep 29, 2006 14:23 UTC (Fri) by ogra (guest, #20098) [Link] (1 responses)

> This is actually pretty exciting. Expect, in a few months, to be able to
> say something like "apt-get install ltsp", and have a working service all
> ready to connect an unlimited number of thin clients to.

thats exactly how it works in ubuntu since the breezy (5.10) release ;)

see https://help.ubuntu.com/community/UbuntuLTSP/LTSPQuickIns...
admittelty it lacked features in breezy (5.10) and dapper (6.06) that the classic implementation offered

with the edgy release (6.10) it will be feature complete and is considered as the base for ltsp5 to derive from for integration into the other distros.
see http://wiki.ltsp.org/twiki/bin/view/Ltsp/Ltsp5 for more info

so you will be able to not only apt-get install it but also yum install it then ;)

Good!

Posted Sep 29, 2006 16:17 UTC (Fri) by dberkholz (guest, #23346) [Link]

Don't forget about emerging it. =)

Does LTSP actually work?

Posted Sep 29, 2006 18:43 UTC (Fri) by kbob (guest, #1770) [Link] (3 responses)

Does the LTSP model actually scale?

The claim is that you can use low-powered computers for the
workstations and run everything on a single high-powered server. Do
the economics of that work? It seems to me that they don't.

If 20 users are sharing 1 computer, then the shared system needs to be
much more powerful than a system that supports one user. Sure, it can
get by with less than 20X the CPU because no user uses the CPU 100% of
the time. But it needs the full complement of 20X the RAM and nearly
20X the disk space.

Further, screen rendering is one of the most demanding jobs a CPU
performs, so if you skimp on the workstations, the user experience
suffers. So can you really skimp on the workstation hardware?
Disk, yes. RAM, yes. CPU/video/net/buses? I doubt it.

Computer prices scale superlinearly with performance. A dual Xeon box
might cost 10X what a low-end Celeron/Sempron costs, but it certainly
doesn't provide 10X the system performance. Maybe 2X, depending on
workload.

Lots of people build LTSP systems using hand-me-down computers for the
workstations. But do those five year old workstations really run any
faster than they would with local disks and a RAM upgrade? You can
buy a lot of upgrades for the price of the server.

So I don't see it. LTSP looks more expensive than an
equivalent-performance set of standalone workstations. Easier to
administrate, sure, but more expensive for the hardware.

What am I missing?

I'd love to hear from someone who actually uses LTSP himself, as
opposed to administrating a cluster for a bunch of undergraduates/
secretaries/call center people or other people who're expected
to tolerate a low-quality computing experience.

kbob

Does LTSP actually work?

Posted Sep 29, 2006 22:44 UTC (Fri) by amikins (guest, #451) [Link]

LTSP can certainly be cost effective.

The first thing to note is that there is nothing that requires the actual 'server' portion to be a single monolithic machine. It can be a cluster itself, which can yield more efficient scaling of processing capacity versus cost. It gets trickier to ensure that task load is distributed correctly, but it's quite feasible.

The second is the utilization of local resources.. In many settings where a terminal server style approach makes sense, very few of the users are actually making use of most of their resources for consistently long periods of time. If every single user needed 100% of their ram, and most of their hard disk space potential, then yes, you'd need to scale the server accordingly. In practice, enough users are going to be underutilizing their portion of the resources that pooling them together is going to be a net win. Per user, you won't need as much ram and hard disk space as you would locally, both because of the above factors, and because of duplicated resources.

Additionally, there's data integrity issue. If all data is stored in one central location, extensible redundant storage becomes more managable.. And it's amazing just how much disk space really goes unused in a lot of 'low end' workstations.

Does LTSP actually work?

Posted Oct 5, 2006 23:05 UTC (Thu) by hazelsct (guest, #3659) [Link]

On modern hardware (within the past 5 years), the load of 20 users running things like evolution and firefox is not hard to bear.

Yes, you do need more RAM, but nowhere near 20X. Keep in mind that your RAM calculation ignores overlap in application binaries, shared libraries, and memory caches of data files, icons, etc., each of which needs just one instance in memory to cover all twenty users.

Does the LTSP model actually scale?

Posted Oct 8, 2006 7:59 UTC (Sun) by anton (subscriber, #25547) [Link]

Yes. We have been using X-terminals (not LTSP-based, but that does
not matter for answering this question) for 14 years. At the moment
we have about 25 X-Terminals for students, and right before deadlines
they all connect to one of the following two single-CPU machines: a
2.26GHz Pentium 4 with 2GB of RAM, or an 800MHz Alpha with 1GB of RAM
(slow by todays standards). In addition to the students on the
X-terminals, up to 60 students log into the machines from their homes
via ssh. The machines handle the load just fine, without significant
degradation of the user experience.

However, it depends on which software the users are using. Our
students mostly run an editor and compile and test their relatively
small programs now and then; no fancy Gnome and KDE applications. If
they used memory hogs, we would have to upgrade the RAM on the
machines; e.g., we upgraded the Pentium 4 from 1GB to 2GB when we
expected them to use Eclipse.

Most of our staff is also using X-terminals, using a wider range of
software (e.g., Mozilla, OpenOffice), but we don't concentrate as much
on one machine as the students.

There are some things that you just cannot do across the X-terminals,
like play some modern 3D game (although we did use the ACM flight
simulator with X-terminals a decade ago); not sure what else cannot be
done, because I never hit these limits.