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Re: AT&T -> Qwest ... Localpref issue?
From: PC <paul4004 () gmail com>
Date: Mon, 8 Aug 2011 10:17:07 -0600

I don't like it as it's a slower to converge solution, but look into BGP
conditional advertising.

Or better yet, tell AM you want to move to the "Qwest" internet product.
You want to peer with AS 209.

On Sun, Aug 7, 2011 at 7:30 AM, Graham Wooden <graham () g-rock net> wrote:

 Thanks Paul.

Localpref with Qwest on my AT&T prefixes was 100 until last week ... So my
prepends to balance between the two was working just fine for the past 2
years or so.
My announcements to CenturyLink to Qwest are coming out as 100.

I am not a direct customer of Qwest, so sending the community of 209:70
won’t work (already tried that).  I am a direct customer of CenturyLink and
unfortunately the two networks haven’t really come together as one just yet.
   I sent a note to AT&T – maybe the can help do something, as I reviewed
the communities with them and I am already doing what I need to do.

The main problem here is that our CenturyLink connection is pure crap ...
Even originating routes from their network, I had them take our AT&T (the
other transit at this particular POP) - faster and less hops (go figure).
 At our other pops with more than 1 transits, we like to utilize both as
much as possible.

Contract is up in December ... can’t wait until it’s gone.

On 8/6/11 11:57 PM, "PC" <paul4004 () gmail com> wrote:

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:

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 () 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

Any insight would be great. I haven’t reached out to AT&T or Qwest yet.
Curious if this is a bigger change than just me.



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