useful bgp example

Jeff Harper jharper at first-american.net
Wed May 19 18:37:32 UTC 2010


> -----Original Message-----
> From: Jared Mauch [mailto:jared at puck.nether.net]
> Sent: Wednesday, May 19, 2010 1:29 PM
> To: Jeff Harper
> Cc: Deric Kwok; nanog at 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





More information about the NANOG mailing list