[c-nsp] RES: conditional bgp default-originate

[Jon Lewis]

On Thu, 14 Aug 2008, Hank Nussbacher wrote:

> I have tested this and it is working at a specific customer:
>
> neighbor 10.100.80.7 default-originate  route-map track-Broadwing
> neighbor 10.100.80.7 distribute-list nothing-else-plus out
> !
> ip access-list extended nothing-else-plus
> ! Insert any nets you wish to announce here
> deny   ip any any
> access-list 50 permit 216.140.0.0 0.3.255.255
> !
> route-map track-Broadwing permit 10
> match ip address 50
> !
>
> You want to pick a network inside your upstream that will never go away and 
> if it does, that means their backbone has gone down.  Do a few 
traceroutes 
> and you will quickly figure out what are their backbone CIDRs to use.

That's basically what I ended up with yesterday in the simulator.  My 
problem with it is, without inside knowledge of my upstream networks, how 
do I know which routes will never go away or never even just change mask?
To be safer, if I end up doing this, I'll probably put half a dozen or so 
networks from each upstream in the access-list.

----------------------------------------------------------------------
  Jon Lewis                   |  I route
  Senior Network Engineer     |  therefore you are
  Atlantic Net                |
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