Load Balancing - Nice and Easy - no BGP, no isp help.

[Lowell Gilbert]

Ovidiu Ene <ovidiue at unixware.ro> writes:

> Hello friends
> 
> I am trying for a while to make a load balancer under FreeBSD
> 
> I would have: 3 nics, ISP1 nic, ISP2 nic and LAN nic.
> What i've done until now, after reading lots of posts, googling for a while:
> 
> - I've suceeded to setup an outgoing load balancer with pf, it works
> perfectly but only for outgoing traffic;
> - I've noticed that almost everybody thing that it cannot be done load
> balancing with BSD of incoming and outgoing without help of that both
> ISP (BGP)
> - I find hardware with proprietary OS/firmware that can do load
> balancing without support of ISP. Some are cheap (300$), but at review
> does not know to load balance incoming traffic (break functionality of
> some pages accessed, since some of load is on one interface, some of
> other, works corectly only if i setup to come some type of traffic on
> one interface, some of other (for example trafic via port 80 on one
> nic, ftp traffic on the other), also are expensive hardware load
> balancers (over 1000$) that... i am asking myself how it works,
> without help of isp.
> - I've found somewhere that it can be done load balancing but not with
> one box with that 3 nics, but with 3 boxex, because (that article i am
> "insipring" said that every box has just one routing table) because
> can be created a virtual server that with handle routes from that 2
> boxes.
> - People told me that in Linux load balancing cand be done, 3 nics, 2
> external, one to Lan, with iptables. Here is a short article:
> http://linux.com.lb/wiki/index.pl?node=Load%20Balancing%20Across%20Multiple%20Links
> 
> So, my question is, if some people made it (in expensive hardware that
> did have the same OS, maybe even FreeBSD, and proprietary algorythms)
> and in Linux it can be done (people told me, i've read articles and
> also so it here, where i live) why it cannot be done under FreeBSD?
> I guess it can be done, I want to do it with FreeBSD, and want to
> obtain same performances as with Linux.

The only specific example you gave was the Linux one.  And that one *is*
doing load balancing on the outgoing side.  I doubt it's very
different from what you did with pf.

> What is your opinion about that? What should I do? Anybody suceed in
> making load balancing work that way?

I don't believe anyone has.  Or can, for that matter.  Aside from
choosing addresses for outgoing connections, you have no control over
what incoming link a peer outside your network will use to communicate
with you.  Unless the upstream providers are cooperating, of course.