[gentoo-user] nfs over (lvm over nbd) ?

[Raph]

Hello,
I'm currently trying to setup a network with
a storageless server.
There are 20 computers (2x1.6 Ghz, 1GB RAM, 160GB sata)
and 1 more (outside the room) with the same hardware
(so no real "server"). The whole is connected
with 10/100 ethernet.
Of course, and so sadly, there is not a penny...
In order to make a network where any user can access
his datas whatever the computer he uses, I'm thinking about
the following kind of configuration :
- Each client (one of the 20 computers) runs a MBD daemon
which shares its HD to the server (the 21st) over the
ethernet.
- The "server" handle the 3.2TB in a volume group and
create the logical volumes with LVM
- The "server" also run a NFS daemon
- Then each client can grab it's data through NFS.
- happiness ... ?
------
I never did such a setup but already see a couple of
problems :
- each client need some private HD space to, at least,
boot enough to let the NBD daemon start.
- $10 question : if 20 users login, will the ethernet
be fast enough to support the load ?
------
I though about a more manual way (rsync at login/logout)
but it implies versionning and above all distribution and
mirroring, ... so appears less reliable at first look.
Also I can't imagine a way to abstract the storage with lvm
with a distributed syncing at log{in,out}.

I would greatly appreciate any ideas, critics, ...

Raph

PS-1) Not a penny means that it's already a pain to afford
a 30€, 24 ports switch (the 20 computers were given last year)
So the N.10³ "sata bays" are nothing else than dreams, here.

PS-2) I already saw some subjects outside the specific
gentoo scope on this list but if this one really makes
no sense here, please just kindly precise it so I will
conceal forever :)