[K12OSN] Load balancing on ltsp, successful/failed attempts?

Les Mikesell les at futuresource.com
Mon Apr 19 13:13:16 UTC 2004

On Mon, 2004-04-19 at 03:55, Daniel Hedblom wrote:

> I have just ordered two more servers and i want to try out real load
> balancing on ltsp. In my calculations it is much cheaper to byu two fairly
> standard one cpu 3Ghz scsi servers than to buy a dual CPU server.

I'd expect that not to be true by the time you add enough RAM to
both servers to account for the program executable and disk
cache that would be shared in a single server, but you do
see bargains on lower end equipment more often.

> Have anyone tried load balancing and was it successful, what did you do
> and what didnt work?

There is always brute force: put the terminals on separate or
vlan'd switches behind each server, but you don't get failover
that way.  I haven't tried this, but in theory you should
be able to put the servers on the same subnet with different
addresses and split the DHCP range between the servers.
Whichever one answered faster would supply the address and
boot options to the terminal. This would probably require
adjusting some assumptions in the k12ltsp setup.  Hmmm, you
could probably get away with overlaying 2 subnets on the
same wire so the only change needed would be the inside
address of one server.  Then you just have to see if the
machines win the race at random or how much load it takes
on one before the other starts winning.  You'll need a
separate home directory server to make this work transparently
and fail over nicely.

  Les Mikesell
   les at futuresource.com

More information about the K12OSN mailing list