[quagga-dev 4699] Re: Linux and BGP multipath

[Paul Jakma]

On Wed, 25 Apr 2007, Paul Cupis wrote:

> Is there currently support for BGP multipath in Linux/Quagga?

Define what you mean by BGP multipath. I can think of two kinds:

- a (single) BGP Next-hop resolving to multiple IGP/static nexthops

or

- a single BGP route (ie target prefix) resolving to multiple BGP
   next-hops.

Usually people mean the former, but there's been a question recently 
that meant the latter.

> If not, what needs to be done to implement this functionality - is 
> it in kernel-space or within quagga?

Neither require kernel work (presuming multiple-path routes are 
supported by your kernel - they are on linux).

The former requires work in zebra to allow recursive routes to 
resolve to multiple next-hops, i.e. the zebra RIB needs to updated.

The latter requires work in bgpd.

regards,
-- 
Paul Jakma	paul at clubi.ie	paul at jakma.org	Key ID: 64A2FF6A
Fortune:
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