useful bgp example

Dan White dwhite at
Wed May 19 18:58:38 UTC 2010

On 19/05/10 13:37 -0500, Jeff Harper wrote:
>> -----Original Message-----
>> From: Jared Mauch [mailto:jared at]
>> Sent: Wednesday, May 19, 2010 1:29 PM
>> To: Jeff Harper
>> Cc: Deric Kwok; nanog at
>> 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
>> 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,
>network mask
>ip prefix-list NETZ description The networks we advertise via BGP
>ip prefix-list NETZ seq 10 permit
>ip prefix-list NETZ seq 1000 deny le 32

You should be using for documented examples,or at least private
space. Configs like this tend to get cut and pasted into routers and get
changed only when they don't work.

I just had to change a router config a couple of months ago that a consult
had set up using and, for point to point links.

Dan White

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