A Computer Lab with No Windows, Part II

Finishing the lab setup, the benefits of OpenOffice.org and looking to the future.
Further Development

With the existing 32-bit CPU (Xeon or AMD MP series), the maximum amount of RAM on the server is limited to 4GB. When a bigger--say, over 40 workstations--computer lab is needed, a 64-bit CPU such as the AMD Opteron should be used.

The performance of SCSI drive is great but the price tag is still high. I have tried SATA drive on workstations and found the performance is much better than the parallel IDE and the price is about the same. To build a cheaper and better Linux terminal server network in the future, I would like to try a dual AMD Opteron CPU with 8GB or more of RAM and a SATA drive.

If anyone has set up a terminal server supporting more than 40 users, I would like to hear his/her experience for future improvement.

______________________

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second cable

online-klip's picture

You can set quotas for users. N.B. I used ata100 with the Soltek mobo and it rocks. Unfortunately, the mobo comes only with one ATA133 cable. It is best to put the second drive on a second cable.

online-klip

thanks

CropLogic's picture

Your post brought zen to my C. line

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Ha! How much time do you wast having to fix any problem that arises? I am dual booting with Linux on two computers, and it seems that one is always having some sort of problem. I'll stick to Windows, thank you very much. Less hassle, more programs, and it JUST WORKS!

Linux just keeps going and going...

Anonymous's picture

My experience with Linux is that there may be one or two problems at installation and after a couple of hours of effort there is little to do with a Linux system except backups and managing users. My school's lab ran all winter without a crash after we installed Linux. Using that other OS, we had crashes hourly and used to do defensive re-boots and ghosting. That other OS is a waste of time and resources.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Depends on how much time you put into learning Linux! If you havent got time and just no a bit about computers/OS's then windows is bound to be better for you!

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

But of course, it helps to have the cash handy ;-)

suggest a minimum system config

Anonymous's picture

i wish to set up computer lab for my school . since computer hardware costs too much here (kerala,india) and nobody to help us by supplying free pcs please suggest a minimum configuration for the server which will serve five to ten clients we wish to run open office , kde and gnome and other programing languages . how much ram is required and what processor i should go for (an athlon 2000 cost 100 $ here and RAM 256 @ 70 $) will ata harddrives give resonably good performance. and i dont want to give people a bad experiance on linux
where can i find free educational programmes for linux (like encyclopedias ,and tuters )

Server Sizing for LTSP

Anonymous's picture

Hello,

You might want to read the article at:
http://wiki.ltsp.org/twiki/bin/view/Ltsp/ServerSizing

RE: suggest a minimum system config

Peter Strasiniuk's picture

hi there, i understand. for good performance you need good hardware for linux as well... but with linux you get more power with less costs... cu@all ps

Re: suggest a minimum system config

Anonymous's picture

50 magabytes per client is a useful number. It should probably be something like 128 mB + 50 mB/client as you cannot run the thing on 0 memory for 0 clients!

Here, you can graph size of the memory modules vs price to see what is most economical. I find 512 mB modules cheapest.

If you can pick all your parts, I would suggest this list:
nforce2 mobo - Soltek 75FRN2-L is pretty cheap. You get some extra speed using two memory modules

CPU - AMD a 2000 would be decent, but if you are hard up for cash, a Duron will do. Anything up to 2500 should give pretty good price/performance.

RAM if you use nforce2 2 X DDR333. 266 will do almost as well.

Discs - try to get two and install in RAID 1. e.g. 2 X 120 gB gives 120gB of storage with some redundancy and speed up. You need a few gB for the system and some for each user. You can set quotas for users. N.B. I used ata100 with the Soltek mobo and it rocks. Unfortunately, the mobo comes only with one ATA133 cable. It is best to put the second drive on a second cable.

NIC - 100baseT is much better than 10baseT. If you have only 5 clients, you can install 5 NICs on the server so that each client has a 100 mbit/s path to the server. For 10 clients, you would need an additional 5 or 8 port switch. Setting up the server is a little more complicated for multiple NICs, so, if this is your first, you might use a single NIC + switch (a hub would give reasonable performance in such a small network). I find cheap Encore or Realtek compatible NICs quite reliable. Some have BootROM socket which could be used on the clients.

The server needs a cheap graphics output for setup. You could borrow a card from one of the clients for setup. You can buy some mobos with graphics on board. Note AGP cards come in 2/4/8x and some are not compatible with some boards. Be careful to get a match as you could damage card or board.

See a report on installing my server at
http://www.skyweb.ca/~alicia (.pdf at bottom)

See also the Skolelinux/DebianEdu project

Anonymous's picture

Great article. For those interested in out-of-the-box LTSP, pls. also take a look at the Skolelinux project

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

I teach high school C++ in BC, Canada. I am a FOSS Free Open Source Software advocate. I would love to try this with my lab. I run linux at home so I am not a newbie. But I don't have experience as a linux admin. We are still using Windows NT with 233Mhz PII's. I think this would be an excellent idea for the lab. Just curious if a server would handle all the kids trying to compile something at the same time? I think articles like this are fantastic!!! I have emailed it around the district. I think this is the future of K-12 education. Can't wait for LTSP with kernel 2.6!!

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Hello! I teach high school computer science/computer engineering courses at Monarch Park Collegiate in Toronto, ON Canada. Have been running a Linux lab for more than 2 years, using Open Source software only! We cover C, C++, Java, Free Pascal, etc. We use Povray, Blender, Gimp for computer graphics/modelling, animations, etc. In fact, I don't see a need for anything else! We're running Mandrake 9.2 at the moment, with a few servers running Red Hat 9.0. Truly refreshing, after leaving windows a few years ago! =)

Take a look at some of the schools around the world using linux:

http://casestudy.seul.org

re: Re: A Computer Lab with No Windows, Part II

Callipygous's picture

What about Inkscape?

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Unless the teacher says, "Go!", it is not usually a problem. CPU time rises to 100% or nearso for a few seconds at a time. If two happen to go at the same time they each get 50%. It would be different it they were all recompiling the kernel on the same day, but, unless your students are very different from mine, that is unlikely to happen. I use PASCAL and compilations are split seconds for a small program.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

I would like to be able to communicate with you if you are a teacher with this setup. I have approval as of today to start a pilot project from my admin. I would be interested in more of the implementation info, if you would like to share your experience. Check out my website if you want to send me an email.
http://fltk.org/links.php?V219

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

We are using Linux as our webserver in our elementary school. . It's the first time Linux has ever been used, and I rely on advice and expertise from people in the community.

I'd like to branch out and do even more with linux (SQUID would be very nice).

We mainly run OS X, but you really can't beat the price for Linux!

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

SOUND.
Hello,
first - very good article.
can anyone tell me something about success with setting sound on ltsp.
which sound server do you use, any hints in configuring it.

My experience with a business LTSP setup

ringerc's picture

I run an LTSP setup for work. It was originally approved so that all our basic-needs users can be provided for cheaply and easily, but has expanded over time as it's proved reliable, fast, and cheap. When we first decided to run an LTSP system, we went the whole hog on the server side - and have not regretted it.

We bought a dual 2.4GHz Xeon with 2GB of RAM and Serial ATA RAID (3ware Escalade 8500). The OS and /var (databases + mail) are stored on a RAID 1 array (2x80GB SATA), while user data is stored on a 3x120GB RAID 5 array (soon to be 4x250GB).

The server is, in addition to being a terminal server, the core server for our network - NetATalk (Apple) and Samba (Windows) file sharing, Cyrus IMAPd for IMAP/POP, sendmail for SMTP, MySQL, etc. We also have hundreds of gigabytes of regularly accessed "hot" archival data on the system. It handles all of this, and 20 terminal users, without any noticeable slowdown. Real RAM usage rarely goes above 750mb, and I expect I could pack at least 60 users onto it - and many, many more with more RAM.

The workstations are P133s with 32mb of RAM and S3 video. GOOD VIDEO CHIPSETS ARE VERY IMPORTANT - AND S3 IS NOT A GOOD ONE. A p133 with a GeForce4 MX feels _much_ faster than a P300 with an S3 video card. Keep this in mind when buying workstations - the video chipset (or XFree86 driver quality) seems to be the #1 performance factor. It's also important for the useability of many apps to have at least a 1024x768x16bit display.

Make sure you have good NICs - we use Intel EtherExpress Pro/100s with PXE-enabled flash here.

Additionally, if you want quick user acceptance of the new system, providing quality monitors and optical mice with scroll wheels seems to help a _lot_, especially if they were working with blurry monitors and worn out serial mice before. Users notice and care about different things to many techies - "wow, my screen's so /nice/" will be the deciding factor for many (not quite clicking that the screen is nice on any computer). We actually introduced the system progressively, and by the time about 1/3 of the users had been moved over from the 486/16MB+Win95 systems the rest were almost banging down my door. Why? Because when we upgraded the users' systems, they got quiet desktops, new screens, and nice new mice. The OS? They didnt' care so long as it did what they wanted, which it did.

Overall we've been very satisfied with our system. We'll be migrating the users from XFCE4+Mozilla+OO.o to GNOME2.4+Evolution+OO.o very soon, as the latter is much more useable and much more consistent. Evo is also much less buggy than Mozilla Mail. XFCE4 was great for our basic users, as there were only a couple of things they could click on and it was easy to centrally configure - but now we're moving the journalists onto the system and they want a bit more power. It seems better to put everyone on GNOME than have two diferent environments to support.

I strongly recommend 3ware SATA RAID cards to anyone building such a server, too. They're wonderful in that while they're fast hardware RAID cards, you can add huge amounts of storage for peanuts. If you put the OS, /var and /opt on a couple of Western Digital Raptors (73GB 10,000 RPM SATA drives with TCQ) your server will probably just /fly/. I'm getting good enough results with the current 7200rpm non-TCQ drives we're using, but I hear great things about the Raptor series. They're also _much_ cheaper than SCSI, and according to folks like storagereview.com, they're at least as fast.

Also, for things like terminal servers, the difference a second CPU makes is incredible. We actually have SMT/HyperThreading enabled, so we get 4 virtual CPUs - and absolutely amazing performance when multitasking. This is good when you have 20+ active users doing highly interactive tasks. I strongly recommend choosing an SMP system - they're not /that/ much more expensive, and will prove to support a lot more users.

Also, I second others' comments here: your Xeon should go above 4GB of RAM. Most Xeon boards go to 8GB or 16GB, with the Xeon MP boards sometimes going higher still. We have _lots_ of room to grow with ours, as our server will happily support at least 8GB of RAM.

Speaking of RAM - more is better. 2GB is a good start. What isn't in direct use by processes will be used as disk cache, reducing the load on your disks and making performance very snappy.

One other thing that's of note is that AFAIK Linux will actually only load the binaries and libraries for a program once. You have _one_ copy of libc6 in memory, _one_ copy of OpenOffice, etc. In addition to the memory savings (extra users after the first one cost a lot less in memory, esp with GNOME, OO.o and other memory-hungry apps) you'll notice that apps start a _lot_ faster for the second and subsequent users, because they're already in memory in a useble form.

One other experience: I found that I needed to steer clear of GDM2 in favour of KDM, as GDM2 sometimes hung and stopped responding to connections. Perhaps this has been fixed since Red Hat 8's GNOME (which we're currently using).

On the business side, our LTSP deployment has saved us a lot of money. From AU$1200 for a workstation (with OS and virus scanner) we can now get new workstations for $500 with a decent monitor, or as low as $200 for a quiet, cleaned up 2/h PC. We no longer pay OS upgrade fees, we don't have to worry about CALs, and the (very affordable - thanks to the wonderful ClamAV and MimeDefang developers) virus scanner running on the server is only to protect the legacy win98 users on our network.

Craig Ringer
IT Manager
POST Newspapers

Re: My experience with a business LTSP setup

Anonymous's picture

This article is very informative as well as inspiring.

- jaranza

Another note

ringerc's picture

As my memory seems to be failing me today, another little addition to the above:

Gigabit ethernet is well worth it, and gigabit switches are cheap. A PCI-X gigabit NIC and a 24 port 10/100 switch with 2 gigabit ports probably won't cost much more than AU$1000. This is money well spent, as your network will scale extremely well as you add clients. It also makes network backups easy to do with minimal disruption to other users.

Craig Ringer

Also...

ringerc's picture

I strongly suggest you set suitable memory limits in /etc/security/limits.conf. I use:

@users soft rss 512000
@users soft memlock 256000
@users soft as 768000
# Set to 7168 by RH defaults
#@users soft nproc 5000

Just to stop users from forkbombing the system accidentally, or a runaway process from eating all the physical RAM and forcing the system into heavy swapping. It works extremely well. Adapt the above, of course, to your memory allocations etc.

Multiple Network Cards

Anonymous's picture

I'm about to experiment with using 2 network cards for the same LTSP terminals. This came about because I was originally going to have a 192.168.1.x linux network which was to link into the Windows 192.168.0.x network via the LTSP server. Now, using the 1067 ports for DHCP this is no longer necessary, so I've got two cards in the server, both connecting into the same switch.

Is there any benefit in setting up LTSP so that SERVER, XFS_SERVER and SYSLOG_HOST are all on 192.168.1.1 and XDM_SERVER is on 192.168.0.120? (Both IPs are the same server) We don't want to splash out on gigabit ethernet, so I wondered whether the above would lighten the load on the server's network card.

Cheers
Simon

Re: Multiple Network Cards

Anonymous's picture

I don't see any reason why that shouldn't work. OTOH, you're probably connected through a 100mbit switch anyway, so unless you workstations are plugged _directly_ into the same switch as the server you won't see any benefit. Some realyl crap switches also have very limited backplane bandwidth, which will also reduce your results.

That said, gigabit is cheap ( I paid AU$1000 for a quality managed 24x10/100+2xGigE switch last year) and fuss-free. Gigabit NICs are even becoming standard in desktop PCs.

Craig Ringer

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

What is the M$ Terminal Services equivalent on Linux?

X-Win does do the windows emulation and transfer screen display over the network, but does it sustain sessions upon disconnections due to network outage? It really helps in this part of the world where power outages switch off the workstations but if the session is held then the student continues from where they were disconnected due to power problems.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

XVnc is a partial solution, however it works copying bitmap blocks because the protocol knows nothing about the underlying drawing system, so it is slow and flacky.
Security seems to be weak also, as passwords to log on are per server, not per user.

OTOH, I think somebody (Keith Packard?) is working in (or at least planning) detacheable X sessions.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

X11 does not support the survival of an app after loss of contact with the X server, nor does it support transferring apps between X servers. While there is work happening on this, it doesn't appear to be going anywhere fast. X11 doesn't currently do what you want - sorry.

You could use VNC - it's a lot faster with a UNIX VNC server because Xvnc knows _exactly_ what needs redrawing without screen-scraping. It's still not super-snappy and it's still quite bandwidth-hungry - but it will let you retain sessions across a disconnect.

Craig Ringer

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

From Starnet

Pricing, Quotes & Site Licenses
At just $225.00 USD (single commercial license), X-Win32 remains priced 30-65 percent below competing solutions. Volume discounts as well as discounts for Government and Educational users make X-Win32 the most affordable PC X server for every type of customer.

Then there's CygWin
see also CygWin FAQ

May I recommend sudo?

Anonymous's picture

I'd recommend you install sudo to allow root access to the machines. I have been using it for years and I never login as root unless it's something that can only be done in the root user's environment. That way you can limit what people can do as root, and log what, when, and where they do as root.

My $0.02,
Damon

Memory Restrictions

Anonymous's picture

if you need more than 4 gigs of ram you can use a PAE kernel. This will allow the OS (not each invidual application) to address more than 4 gigs of ram, by allowing a logical mapping of up to 64 gigs of ram. However you will take a slight processor hit ~5% due to the overhead from the memory mapping.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Xeons support 64GB of RAM, by the way. Of course it depends on a couple of things - an MP or DP CPU and which chipset you are using.

But definitely NOT limited to 4GB on a Xeon in any case. Xeons use 36bit addressing. The DP can use 16GB and the MP can use 64GB.

Check it out for yourself.

PAE sucks...

adt6247's picture

Yes, the Xeon can use 36-bit addressing using a technique called PAE (Physical Addressing Extensions). Using this, however, slows down memory access times, because each request takes 2 clock-cycles to send rather than one, seeing as a 32-bit CPU can't process a 36-bit number in one op. The Opteron, particularly at current pricing, is a superior option if you want to go with lots of RAM. Plus, with 64-bit Linux, there are some speed advantages on the AMD64 platform -- most notably due to access to double the number of GPR's. Honestly, most apps won't get a significant boost from 64-bitness, other than access to more RAM and GPR's.

PAE sucks - how do I get rid of it

fredkarm's picture

I bought a new computer (Xeon processor) and put the /PAE option. The computer is slow, might be the /PAE. Tried the /NOPAE /NOEXECUTE=always off. Boot file takes it, but when I restart and check windows (MYcomputer) the Physical Address Memory still shows 8 GB. How do I remove this beast?

Re: A Computer Lab with No Windows, Part II

RobertP's picture

The new dual Xeon server, with 2 2.4GHz CPUs, 4GB of RAM and an Ultra320 SCSI hard drive (no RAID), supports 28 diskless workstations smoothly. After entering the user's password, it takes about seven seconds to load up a KDE desktop.

A great way to run a lab, but mine is faster. My kids boot up in 4s! I use a single AMD2500 processor, RAID 1 and dual channel RAM. See http://www.skyweb.ca/~alicia (.pdf at bottom) for details.
RAID speeds things up for this, not slows them down. Very few files are being written but hundreds are read. Most will come from the RAM cache, but RAID 1 over n drives can allow n files to be read at once, a great speed increase.

Intel Xeons have FSB bottleneck according to this:

Anonymous's picture

We were all puzzled why this dual-Xeon system was a bit slower than a good Athlon. I think I found the answer in this article about benchmarking Xeons and Opterons:
http://www.anandtech.com/IT/showdoc.html?i=1982&p=3

The dual Xeons have to share the bandwidth of a 400MHz FSB between them for 200MHz apiece. The single athlon gets 333MHz all to itself. Now, the transfer from HD is via DMA but the stuff probably needs to be moved at least once through the CPU, so , the FSB bottleneck gives a ratio of
333 MHz = 7s
----- ----
200 MHz 4s

Of course, this should not be a problem if the CPUs get a balanced load. These data suggest the load is not balanced.
QED

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Your speed increase may be due to your GigaBit server connection. The author of this article would not be able to follow suit without an upgrade in switches as well.

He could use MRTG to graph the traffic seen at the server to judge if that is indeed a bottleneck or not.

Another option would be etherchannelling.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

That could be part of it. My clients are still 100 base T from the switch, though. Gigabit is becoming cheaper. I was fortunate that the guys who installed my network installed 24 port switches with two gigabit ports for daisy chaining and one was free for my LTSP server. Our switches are
http://www.3com.com/prod/en_CA_AMER/detail.jsp?tab=prodspec&sku=3C17300-US
3com 3c17300 4226t and they are solid.

My NIC is INTEL PRO 1000 ant the price is down to about $35 Canadian.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Actually, this is incorrect. Raid 1 over n drives allows files to be read n times faster, but not n files at once. The nature of striping means a file is writting across n disks to be read in parallel. But each request for a file still only gets that one file (it just reads it from the spread of n disks). Likewise, requesting 5 files stills reads each file in sequence, though n times faster.

Just a clarification.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Riad 0 is striping. We are writing about RAID 1 where you can n drives with mirrored filesystems.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Its great to see Linux supporting your lab!

I have worked with raid1 for a while now. I don't think that you will see a performance loss using raid1. As you note there is a write to each drive for every uesr write. These writes occur in parallel. Also the filesystem usually starts a lot of writes at a time so parallel writes arn't noticed all that much. On the other hand read performance is better since raid1 shares read requests between both disks.

One comment above mentioned floppy disk sneaker net. I have found usb memory sticks the be much faster than floppy. usb floppy runs at about 22kb/sec and memory stick runs at 800+kb/sec in our tests. 64mb memory sticks are inexpensive today and store a lot of data as well. Students can carry around personal backup of their data on a memory stick.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Do the IBM P200s have USB? I've never worked with 300PLs but I don't remember my old company's 300GLs having USB slots. If they did, they were round the back of the box, hardly ideal for students.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Several vendors offer USP panels that plug into either a 3.5" or 5.25" slot on the face of the computer. These can either connect internally to existing USB connections on the m/b, or they can be connected via cable to the actual USB port on the back panel. Also, there are a number of USB mini-hubs that can be purchased relatively cheaply.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

I've installed a modest LTSP setup at my kids' school, with an Athlon 2200+ server, 512mb ram, dual 40gb hard drives. It's running fine with 10-14 terminals, they're all using IceWM for speed and ease of lockdown. (Actually, there are 20 terminals but they can run Linux or Windows)

Today I installed lilo on the remaining Windows computers and used the 1067/1068 option in rom-o-matic so that my Linux DHCP server can co-exist with the Windows NT one. Students can dual boot, selecting local Windows or remote Linux. Printers are shared, and it's all looking rather snazzy.

I have a few things to sort out. One is orphan processes where students can switch off a terminal leaving IceWM running on the server until it's cleaned up. (These processes vanish by themselves eventually, but I want to write a cron script which will check for logged in users and zap any user processes belonging to non-existent users) I don't want a 'logout' option, since I'm using Autologin to tie particular IP addresses to host names and then to login names (ws001 to ws040) If they get the option to login from kdm, who's to say two or more won't choose the same user?

Another is local floppy access. I'm considering putting a Windows machine in the corner, with access to the shared student folder. Then they can copy files to floppy without worrying about mounting/unmounting disks. I'd love to hear of alternatives, especially direct access to the local floppy drive.

It's taken me a long time to gather info on all of the above. There's plenty of info around, but I wouldn't say there's a beginning-to-end document. I'm working on documenting what I've done, I've put together a couple of scripts which might be of use to others. One generates new users, copying from 'ws000' (an unused template), and another updates all users including fixing their Mozilla Firebird settings, generating OpenOffice folders and settings so it uses those from ws000, etc etc.

Cheers
Simon
www.spacejock.com

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Re; Access to local floppy drive :

Try this:
http://www.google.com.au/search?q=cache:UeB5stb_5YUJ:www.ltsp.org/contri...

I used this solution myself and it seemed to work quite well.

Regards,

Ed

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

check out k12ltsp - there is a program (forget the name) that allows local floppy access.

there is even a gui interface for it too!

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

If that's the one I think it is, I got it some time ago and altered the source to prevent deleting and renaming. (Just copy to/from floppy) However, I didn't get the local floppy under LTSP working properly, I have to investigate further.

Cheers
Simon

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

great article, thank you,

a little question:

"Students can bring in their work either on a disk--I enable local disk access"

if users are logged on the server, how do they interact with the local disk? is it a feature avaliable in LTSP? some nfs shares on the clients and some scripting on the server? a file manager launched locally? or what else?

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

I think, "local disk access" means the floppy drive on each terminal.

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Instead of add PATH like you do, try this, it's much more secure

I'm using LTSP as a Java Develpment Server, with six java developers connected to it with six pentium 100 with 16MB of RAM and a PXE network card. In the future, I'll put two more servers, one for production users and another to users get internet related things... No one can copy to each other, this improves the security of my LAN...

If you can, I want to contact you, I'm doing a project for a LAB of my Computer Science curse and I just will use LTSP for it... It will be very userful... thanks...

Contact: Alexandre C Alencar - alexandre at debian-ce dot org

#/etc/profile.d/java.sh

JAVA_HOME=/usr/java/j2re1.4.2_01
JDK_HOME=/usr/java/j2sdk1.4.2_01
export JAVA_HOME JDK_HOME
PATH=$PATH:$JAVA_HOME/bin:$JDK_HOME/bin
export PATH

#/etc/profile.d/java.sh

Re: A Computer Lab with No Windows, Part II

Anonymous's picture

Thank you for your suggestions. You may contact me
at leung@uwinnipeg.ca

CT Leung
Sisler High School
Winnipeg

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