unequal cost load balancing?

[Otto Solares]

On Thu, Nov 26, 2009 at 11:01:37PM +0100, Ondrej Zajicek wrote:
> On Thu, Nov 26, 2009 at 03:07:32PM -0600, Otto Solares wrote:
> > On Thu, Nov 26, 2009 at 09:03:30PM +0100, Ondrej Zajicek wrote:
> > > On Thu, Nov 26, 2009 at 12:54:15AM +0100, KORN Andras wrote:
> > > > Hi,
> > > > 
> > > > we have a 5Mbps symmetric microwave uplink with one static IP and a /30
> > > > subnet. We're contemplating getting an additional ADSL connection to serve
> > > > as backup. If the ISP cooperates, is there a way for me to load-balance and
> > > > fail over between these two connections using BIRD? If so, how?
> > > 
> > > Hmm, load-balancing and multipath is not implemented. The best thing you can do
> > > with BIRD is to have asymetric routing (one link preferred for upstream and
> > > the other for downstream), or prefix based load-balancing (some prefixes
> > > are preferred over one link and other prefixes are preferred over the other
> > > link).
> > 
> > Could you please describe prefering prefixes over one link with an
> > example please? I happen to need this but haven't figured out yet.
> 
> This can be easily done using BGP as a routing protocol - just use
> two BGP sessions, each over one link, export prefixes to both of them
> and set MED attribute accordingly.

Ok.

> I don't know about clean way to do it using OSPF. I have two ideas, both 
> are somewhat crazy:

I don't use OSPF but nice to know.

thank you!
-
 Otto