[c-nsp] Advertising routes Automation

[Anton Kapela]

On Mar 20, 2010, at 11:14 AM, Gert Doering wrote:

> Hi,
> 
> On Sat, Mar 20, 2010 at 02:51:08PM +0000, sherif mostafa wrote:
>> I want to make a script also to manualy advertise or deadvertise 
>> specific segment across one or more links.
> 
> Could you please tell us your network ranges, so I can filter them?
> 
> We're not really interested in having our routers carry your 
> deaggregations.

I second this idea.

However, Sherif, what you should investigate is announcing your covering aggregate routes to all providers, then announcing specific no-export community-tagged routes to specific providers. In this way your aggregate prefix propagates via all upstreams (and makes the internet a better place), and the specific or longer-prefixed routes (presumably for TE purposes) can be controlled, or in effect, isolated to 'attract' traffic inbound from a specific transit 'cone' down-stream of said provider. 

So, make your next email something of a "hey, upstream XXX, what are the available communities that I can use on your network?" -- you can also begin by examining this handy collection of well-known communities:

http://onesc.net/communities/

In any event, don't needlessly de-aggregate crap towards the world, and don't do selective/disjoint advertisements to your upstreams -- it's not as stable (as nailed-up announcements with specific no-export or limited-exports for TE), unnecessarily complex, and will likely fail in interesting and/or hard to troubleshoot ways.

-Tk