[c-nsp] BGP route won't advertise

[Jon Lewis]

On Wed, 27 Feb 2013, Jay Hennigan wrote:

> On 2/27/13 4:07 PM, Jerry Bacon wrote:
>
>> I've tried with and without next-hop-self on R3, it doesn't seem to make
>> any difference.
>
>> ip as-path access-list 10 permit ^11xx1
>> ip as-path access-list 10 deny _11xx1_
>> ip as-path access-list 10 permit .*
>
> You could simplify that to:
>
> ip as-path access-list 10 deny _11xx1_
> ip as-path access-list 10 permit .*   <- Dangerous outbound to transit
> connections.

Or simplify things more by using prefix filters / route-maps on the 
customer BGP sessions to deny/accept+tag routes with communities that tell 
the rest of your network what to do with the routes (i.e. whether a route 
gets advertised to your transit providers, etc.).  That ends up being much 
saner as you have smaller filters in more places rather than monster 
filters at the border where you'll lose track of why things are there.

----------------------------------------------------------------------
  Jon Lewis, MCP :)           |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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