AT&T -> Qwest ... Localpref issue?

PC paul4004 at gmail.com
Sun Aug 7 04:57:47 UTC 2011


Qwest uses 80 for peers; 100 for customers.  As I'm sure Qwest had AT&T as a
peer prior to today (and you tagged as a customer), it probably should have
been 80 since the beginning.  What was the local pref to AT&T before?  Maybe
they found a misconfiguration on a router.

If your only objective is to make your Qwest peering "backup", send
community 209:70 to Qwest and it'll drop your local pref on their network to
70.  This will cause their 80 local pref peering with AT&T to be preferred.

I also suggest you read:
http://www.onesc.net/communities/as209/
and
http://www.onesc.net/communities/as7018/

However, depending on if your network topology and situational circumstances
permit it, it may not be a bad idea to take on-net customer routes for
performance reasons.

On Sat, Aug 6, 2011 at 8:51 PM, Graham Wooden <graham at g-rock.net> wrote:

> Hi folks,
>
> Anyone else noticed a localpref change on Qwest network in regards to AT&T
> prefixes?  I noticed my AT&T assigned prefixes dropping to 80, causing my
> backup transit peering with Centurylink to take preference with Qwest
> originators ...  All was working fine with my prepends .. But not
> anymore...
>
> Any insight would be great. I haven¹t reached out to AT&T or Qwest yet.
> Curious if this is a bigger change than just me.
>
> Thanks,
>
> -graham
>



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