If you are comfortable with your 200-250 user estimate, then
run your calculations based on all of them doing the same thing at the same
time. This won't truly be the case, but you'll end up with a more robust
requirement which will serve you in the long run. I can't speak from experience
with this kind of Moodle installation, but I can speak from vast experience
moving multi-hundred MB MPEG2 files around simultaneously in a WAN environment.
Bandwidth: 250 users x 10 MB (you did mean 10 mega-BYTE as in a downloaded/uploaded
file scenario?) = 2500 MB of data moving up/down stream simultaneously. That's
A LOT of data...even at Fast-Ethernet bandwidth (100Mbps), 2500 MB of data is
roughly 20000 Mb of data, so it would take 200 seconds (3+ minutes!) to move it
all (longer really, since you'll never see 100 Mbps even on a well tuned LAN
segment). If this is what you're talking about, you better be running Gigabit-Ethernet
on your LAN to accommodate that kind of load. In reality, not all 250 users
would be doing something at the same time (some would be idle), and not all of
what they are doing simultaneously would involve moving 10 MB files up/down
to/from the server (reading, typing, etc.). This is your gray area...what will
the REAL maximum bandwidth load be and how do I plan for it?
Server: the user activity load may not be that huge in terms of actual served
pages, others here with clustering experience can speak to that specifically,
but if the scenario is as bandwidth intensive as I outlined above, you're going
to be looking at probably several servers just to accommodate the data
throughput. It goes without saying that they'll need to be fairly hefty boxes.
How hefty? Can't say, again the clustering folks around her might be able to
Sorry I can't give you a "you need this, this, and this" kind of
Good luck...post back if/when you get it up and running and tell us how you
cracked that nut.