[c-nsp] Fwd: Load Balancing two different ISP's

[chip]

On 9/15/06, Ted Mittelstaedt <tedm at toybox.placo.com> wrote:
>
> ----- Original Message -----
> From: "chip" <chip.gwyn at gmail.com>
> To: <cisco-nsp at puck.nether.net>
> Sent: Thursday, September 14, 2006 5:25 PM
> Subject: [c-nsp] Fwd: Load Balancing two different ISP's
>
>
> > On 9/14/06, Paul Stewart <pstewart at nexicomgroup.net> wrote:
> > > If a customer has a 1800 series router for example with two "outside"
> > > ethernet ports.... And two completely different ISP's on those ports -
> > > what's the best way to load balance traffic for redundancy and load
> > > sharing purposes??
> > >
> > > We'll presume that the customer is running NAT of course....
> > >
> > > Thanks,
> > >
> > > Paul
> > >
> > >
> > > _______________________________________________
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> > > https://puck.nether.net/mailman/listinfo/cisco-nsp
> > > archive at http://puck.nether.net/pipermail/cisco-nsp/
> > >
> >
> > Outgoing, from the 1800, 2 static routes should do the trick.  Just
> > make sure that they include the interface.
> > ip route 0.0.0.0 0.0.0.0 fe1/0 isp1.nexthop.ip
> > ip route 0.0.0.0 0.0.0.0 fe2/0 isp2.nexthop.ip
> >
>
>
> That is rediculous and I'm still amazed to see this kind of stuff in
> a forum where people should know better.
>
> Your sourcing packets with an IP address assigned from
> ISP #1, out the interface to ISP#2.  Whereupon they will
> get 1 hop then be killed by ISP #2's anti-spoof filter.
>
> > Incoming...well that's gonna be a little different and going to be
> > tough to get evened out if even possible.
> >
>
> The only way to load balance with 2 different ISP's is to obtain
> your own AS number and run BGP to each ISP and then
> advertise a block of numbers.  The smallest advertisement
> that any BGP upstream is going to take will be a /24
>
> Ted
>

Gah! You're right, when working pretty much with only BGP folks all
day I forgot that fact, just took it for granted.  However, if they
have a /24 or larger space from ISP #1 they could get  ISP #2 to
announce it for them and still wouldn't have to run BGP.  But your
point is well made.

--chip
-- 
Just my $.02, your mileage may vary,  batteries not included, etc....