On Tue, Sep 03, 2002 at 05:26:54PM +0200, Iljitsch van Beijnum wrote:
On Tue, 3 Sep 2002, Jesper Skriver wrote:
Links and loopbacks => IGP
Why on earth does you want your link addresses in your IGP ?
Sometimes it cannot be avoided, due to bad implementation, but why do you need it ?
Routers that learn a route over IBGP need to know where the next hop address for route from other AS points to. Since this can't be a loopback address and you typically don't run an IGP on subnets between border routers in your AS and a remote AS, you need to either set next-hop-self on all IBGP sessions or redistribute connected in your IGP.
Yes, next-hop-self on iBGP sessions is a way to ensure that all BGP routes have a loopback address as next-hop. This also solve nasty issues with IXP's, and someone advertising a more specific of the peering LAN prefix. /Jesper -- Jesper Skriver, jesper(at)skriver(dot)dk - CCIE #5456 Senior network engineer @ AS3292, TDC Tele Danmark One Unix to rule them all, One Resolver to find them, One IP to bring them all and in the zone to bind them.