North American Network Operators Group Date Prev | Date Next | Date Index | Thread Index | Author Index | Historical RE: BGP Default Route
> > On Sat, Sep 14, 2002 at 02:18:15PM -0400, Lupi, Guy wrote: > > > I was wondering how people tend to generate default routes to > > customers running bgp. > > Short answer: don't > > Longer answer: To solve the exact problems you mention below, > only advertise a aggregate block of your own to this customer, > say x.x.0.0/16, then the customer will configure his device > something like > > ip route 0.0.0.0 0.0.0.0 x.x.0.0 > > or > > set routing-options static route 0.0.0.0/0 next-hop x.x.0.0 resolve > > This will ensure that if the border router get's isolated, it will no > longer advertise x.x.0.0/16 to the customer, and the customer > router can > choose a backup path. What if the aggregate is local to the border router? If you want to avoid this problem, you will have to use a route that originates from somewhere away from the border. This is more work than is necessary, IMO. If your border router is isolated, you have a design problem or a failure state that is just as likely to occur(if not moreso) than the border router failing. What I will say is that a "full-table" peer should not get a default route at all. Of course, this isn't very enforcable. In any case, providing a default is not something I would say shouldn't be done, IMHO. Thanks, chris > > /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. >
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