cogent update suppression, and routing loops

Thu Oct 2 16:08:00 UTC 2014

First time I'm seeing it, and I've been a Cogent client for quite a while.

Have you tried getting in touch with their NOC yet? They're one of the 
most responsive in the industry.

On 10/3/2014 午前 01:03, ryanL wrote:
> hi. relatively new cogent customer. is what i've stated in my subject line
> kinda standard fare with them?
>
> i've discovered that when i advertise a /24 from inside a larger /22 to XO,
> (who peers with cogent), and then pull the /24 some time later, that cogent
> holds onto the /24 and then bounces packets around in their network a bunch
> of times for upwards of 8-10 minutes until they finally yank it. this
> effectively blackholes traffic to my /24 for anyone that is using a path
> thru cogent.
>
> example: http://ryry.foursquare.com/image/0e0K1K0t0W2M
>
> it's been a bit of a frustrating experience talking to their noc to
> demonstrate it, but i'm able to duplicate it on demand. even pushing routes
> using their communities to offload the circuit takes forever to propagate
> even on their own looking-glasses.
>
> thx
>
> ryan