[c-nsp] BGP route won't advertise

Jerry Bacon wireless at starbeam.com
Thu Feb 28 13:35:06 EST 2013

On 2/28/2013 10:14 AM, Jon Lewis wrote:
> On Thu, 28 Feb 2013, Jerry Bacon wrote:
>> On 2/27/2013 7:45 PM, Jon Lewis wrote:
>>> 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.
>> I do have filters on the customer BGP sessions, but I have to 
>> disallow his AS from my upstreams, or I become a transit for those 
>> routes.
> So this is a BGP peering...but you're not providing transit?  We have 
> a cummunity string for that.  The above advice still stands.

It's complicated. I am doing transit for this customer, be we have 
common upstream peers, and I need to disallow his other advertisements. 
I'm sure there are better ways to do this, but my real problem is that I 
can't get one of my routers to advertise his routes, while the other one 

Jerry Bacon
Senior Network Engineer

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