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

[Andy Rabagliati]

On Mon, 19 Apr 2004, Les Mikesell wrote:

> > 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.

There has been some very archiveable discussion of large networks
and redundancy in the last 2 weeks - thanks.

        http://developer.skolelinux.no/index.html.en

also has a nice arrangement for the network.

How about the following for a large network with multiple classrooms ?
[ I use classroom for convenience - applies to enterprise as well ]

Each classroom :-

1 switch, 100Mbit, 1 GigE port.

1 application server, two GigE ports.

2 networks - one GigE enterprise-wide network, connecting to one
GigE port on the application server, and hosting mail and /home
for everyone. Monster RAID, enterprise-wide authentication, backup, etc, etc.

Secondary network, per classroom, served by the switch above, to connect
clients to the Application server.

Any classroom could upgrade to N GigE ports on the switch, and N
application servers, each with 2 GigE ports. All application servers are
generic, IDE, and there is a spare on the shelf of the IT dept, and can
be doubled up in classrooms.

The DHCP network is private to each classroom, and thus will only see
the local application server(s). This would be hosted either on a
little box that just does DHCP, NFS (for client / filesystem) and local
lts.conf, or hosted on one of the application servers. client rc.local
scripts changed to do X -indirect instead of X -query.

/home traffic is separated from graphics to the clients.

Now anyone can log in anywhere, but applications are limited to those
available in the classroom.

Cheers,   Andy!