[NCLUG] QoS Question

[DJ Eshelman]

I'm so bummed I missed Tuesday because I was going to ask the following to
the local gurus...

I'm going to be installing a CentOS 4.3 (though if I could get this to work
well on a DSL (Debian) system I'd be pretty happy too...) system that will
be doing spam filtering for a client, but we also want to have this machine
be the checkpoint for all incoming and outgoing traffic... this gets
better... on two T-1 lines (one is going to be FRII, the other a cBeyond
BB2 line which actually has the capability of having more than 1.5Mbit/s,
but since it shares with voice, this would only happen at night).  It's also
quite possible I will be using this machine as a proxy, which hopefully will
help with the routing and cut down on redundant downloads everytime someone
launches Internet Exploder.

I think, thru hours of searching and even some discussions here, that it
should be possible to configure the system for redundant internet
connections - the problem is we also want to implement Quality of Service so
that critical apps (primarily thru Citrix, thank God) can have priority, and
things like web browsing can be lowest possible priority, blah blah blah...
fortunately we don't have voice to contend with (yet) and the Citrix will
drop the VPN traffic significantly.

So my question is this:  given everything above- how would I best configure
the box to be a load-balanced, QoS driven, redundant monster router from
hell?

Success stories?  Horror stories?

I'm excited to see what comes of this project, but if I screw things up...
well, I don't have to fill in the blanks there.

Thanks in advance!

-DJ