On Wed, 2010-05-19 at 13:37 -0500, Jeff Harper wrote:
From: Jared Mauch [mailto:jared@puck.nether.net] Sent: Wednesday, May 19, 2010 1:29 PM To: Jeff Harper Cc: Deric Kwok; nanog@nanog.org Subject: Re: useful bgp example
Nice, but you don't show it as-path filtering your transits out. I frequently see people take something learned from transit A and sending it to transit B, and if it happens to be the backup path in-use for your customer, your transits will accept it and likely pick you as best-path and hairpin through your network.
- Jared
Yeah, I left out the actual prefix-list contents, in hindsight I should have added it, so here it is. Also, a typo in the network statement, lol.
network 1.1.1.0 mask 255.255.0.0
ip prefix-list NETZ description The networks we advertise via BGP ip prefix-list NETZ seq 10 permit 1.1.1.0/16 ip prefix-list NETZ seq 1000 deny 0.0.0.0/0 le 32
FYI: It's got to be either 1.1.1.0/24 or 1.1.0.0/16. And there is plenty more that belongs in an appropriate setup for a realistic usage scenario. This is why we are all advising the OP to get some knowledgeable help. Vince -- Vincent C. Jones Networking Unlimited, Inc. Phone: +1 201 568-7810 V.Jones@NetworkingUnlimited.com