[CentOS] Building an "instant on" X terminal

Wed Apr 14 20:04:26 UTC 2010
Les Mikesell <lesmikesell at gmail.com>

On 4/14/2010 2:38 PM, Stephen Harris wrote:
> I got my hands on a HP t5720.  This was designed as a thin-client
> workstation (originally Windows XPembedded, talking to a Windows terminal
> server).  It's not very powerful, with an AMD Geode NX 1500 (1.0 GHz),
> 256Mb RAM (16MB used for video) and a 512Mb flash "hard disk".
> I plugged in a USB DVD drive and was able to boot "linux rescue" from
> a C5.4 32bit disk, and it basically looks like pretty generic PC hardware.
> So I thought this would be a great device to build as an "instant on"
> type device.  Well, as close to instant-on as possible :-)  This probably
> means a standard C5 build is not suitable (too many processes running;
> would take a while to start up).  So an "X terminal", maybe.
> I look at the LTSP code base, but this looks like it wants to run as it's
> own OS; I already have a C5 server in my house, I don't want to build
> another one (not even as a virtual image).

LTSP doesn't install another OS on the server - it PXE-boots one to 
client devices with just enough to run X as a thin client.  That would 
probably work for you - or whatever local install you can do that 
doesn't start X and once it is up, do 'X -query server'.

> Acting as an X terminal, I'd guess the 256Mb RAM should be sufficient;
> it won't be processing much beyond the display locally (although I might
> want to enable ssh and add a locally connected printer).  The root disk
> could be local (512Mb flash) or by NFS.
> What do people recommend for building this?  What would have the quickest
> power-on-to-ready time?

This probably isn't what you want, but my favorite for quick access is a 
windows or mac laptop that handles sleep mode gracefully and let it 
sleep instead of powering off.  Then when it wakes up and gets a network 
connection (in a few seconds), fire up the NX client from 
www.nomachine.com to connect to a freenx session on your server - which 
you can disconnect and re-connect as needed with everything on the 
desktop still running.  Some of the more current linux distributions 
might handle sleep mode but you'd either have to install a local window 
manager or work to get it to run the nx client in a bare X session.

   Les Mikesell
    lesmikesell at gmail.com