> I have to grow the system from a capability of 250K
> msg/day up to as much as 2.5M/day. I have to add
> virus detection, spam filters, and seperation for
> an encryption trunk. I'm assuming as many as five boxes
> in the cluster - I will have the baseline system
> online while I do this and then use the baseline as
> a backup when I switch over.
I'd guess that in this case, virus scanning may be the crippler. At 2.5
million per day, that's an *average* of 6 per second per machine to scan
and deliver. Accounting for peak traffic periods, each machine could
conceivably have to scan 30-60 messages per second to keep up with traffic.
Depending on the virus scanner, that may (or may not) happen.
You may want to consider dual-processor boards. It's much cheaper to
build the box with BP6 motherboards and dual celerons than to put together
two single-CPU machines. That way, you could at least have two virus
scanning processes going in parallel.
steve
