Hi Jen, You can do that. All of your traffic for the /24 will come to you via ISP3 as this is a more specific match than the /19 it is part of. If you drop your link to ISP3, then your /24 traffic will then be received via one of the /19's you advertise to ISP1 & ISP2.
If this is your intention, then go for it. No need to also advertise the /24 to ISP1 & ISP2 unless you want some of the traffic for that /24 to come inbound on those links. regards, Tony. >________________________________ > From: Jennifer Pruett <[email protected]> >To: [email protected] >Sent: Thursday, 19 July 2012 3:28 PM >Subject: [c-nsp] Route Aggregation and Deaggregation > >Good day! > >Question for any BGP guru's; we have a couple of ASR routers as our border >routers which are advertising a few /19's. The question is not directly >related to the ASR hardware, but the >process and best practice of aggregating PI assigned space. If we advertise >our /19's via ISP1 and ISP2 and then introduce ISP3 and only advertise a >/24 from one >of the /19's, do we have to deaggregate the /19 that the /24 was pulled out >of to accommodate the /24 that we would advertise via ISP3? What are the >ramifications of >such actions? > >Thanks for your time >Jen >_______________________________________________ >cisco-nsp mailing list [email protected] >https://puck.nether.net/mailman/listinfo/cisco-nsp >archive at http://puck.nether.net/pipermail/cisco-nsp/ > > > _______________________________________________ cisco-nsp mailing list [email protected] https://puck.nether.net/mailman/listinfo/cisco-nsp archive at http://puck.nether.net/pipermail/cisco-nsp/
