Re: cyber cafe

["D. Cooper Stevenson" <cooper cooper stevenson name>]

On Wed, 2005-11-02 at 00:26 +0100, Rakotomandimby Mihamina wrote:
> Hi,
> 
> A cyber cafe manager is going to renew all his hardware, and he would be
> interested in switching to Linux.

Outstanding.

> I would like to introduce Fedora/GNOME to him.

Okay.

> The only missing thing is the time counter.
> If I could find a "time counter", it would be ok.

Understandable. 

> There would be one user per computer.
> All clients coming to the cyber cafe would log in as "computer1" on the
> first computer, "computer2" on the second and so on....

[snip]

> So the question is:
> - How to make an executable to run when an user logs in ?
> - How to make an executable to run when an user logs out ?

We know that time tracking is important for your cyber cafe manager.
Implicit in your message are several other important factors to
consider; a few are as follows:

  - A high degree of reliability
  - A high level of Administrative control
  - Administrative simplicity

Basically you're talking about a concept known as "utility computing."
First conceptualized by Sun and IBM, utility computing is a method of
purchasing computer resources like, well, a utility. At the end of the
processing job, the client would receive an invoice outlining CPU time,
network bandwidth, mass storage consumption, etc.

If you've read this far you're likely receptive to thinking "outside the
box."

What would happen if all the clients connected to and ran their
applications from a central server? Yes, I am talking about thin
clients.

But there's a new dynamic here. Consider Xen, a para-virtualization
project by Cambridge University that runs multiple virtual computers on
the same machine. Xen virtual computers run at very close to native
speeds while the users effectively get their own PC. 

In your case, you're mostly concerned about accounting issues. XenStat
can handle this.

As your needs grow, the Xen servers may be clustered.  Live migration of
virtual machines from one node to another takes only seconds and is
nearly imperceptible to the end user.

All this buys you the ability to have very quite PC's in the cafe (not a
huge factor on Friday nights) without moving parts. The client images
are on the server, this minimizes maintenance. 

I think that one of the nicest things about Zen is that--for all the
power it provides--it's not that big of deal to set up. I did so on my
Gentoo server and thought, "there's no way it could be that easy," but
it was!

You may review Xen here:

    http://www.cl.cam.ac.uk/Research/SRG/netos/xen/

Best Regards,


Cooper "Coop" Stevenson
President
GenCom
http://www.gencom.us

   
One of the n 
> 
> Using GNOME on Fedora Core.
> Thank you.
>