204.17.16.0/20 Unreachable via Comcast ASN 7992; Looking for Help or Contacts

Fri Aug 9 18:42:46 UTC 2013

Interesting; instability due to reaching this table limit? Good info!

On Thu, Aug 8, 2013 at 10:39 AM, Tony Tauber <ttauber at 1-4-5.net> wrote:

> It's a fair question and had nothing to do with the other network (TW
> Telecom, in this case, not TIme Warner Cable).
> Sorry for not filling in details sooner.
>
> We recently needed to adjust the scale profile on some of our Cisco ASR9k
> trident chip (80gig) Line Cards as we reached . The default profile only
> supports up to 512k routes and will notify that CEF has run out of
> DATA_TYPE_TABLE_SET space as a result. The profile change required (profile
> 13) requires a reload of the chassis. please be advised.  You might want to
> review with your local support team.
>
> The symptom involved BGP neighbor instability and unreachability of some
> destinations.
> Shutting down that particular BGP session was a temporary work-around
> until the adjustment could be made during a demand maintenance window to
> minimize disruption.
>
> Thanks,
> Tony
>
>
> On Wed, Aug 7, 2013 at 5:31 PM, Phil Fagan <philfagan at gmail.com> wrote:
>
>> BGP Noob question here; but wouldn't Time Warner not recieve a prefix if
>> it
>> wasn't reachable? Is this an artifact?
>>
>>
>> On Mon, Aug 5, 2013 at 11:32 AM, Chad Reid <Chad.Reid at apollogrp.edu>
>> wrote:
>>
>> > Thanks for the assistance everyone. This issue was resolved by shutting
>> > down a BGP peering session between Time Warner and Comcast. --Chad
>> >
>> > Chad M. Reid, Network Administrator II
>> > Work Hours: Sun. - Tue. 6AM-6PM and  Wed. 6AM-3PM (MST -7)
>> > Apollo Group | IT Services │ IT Operations Center (ITOC)
>> > 4025 S. Riverpoint Parkway │ MS: AA-M002 │ Phoenix, AZ 85040
>> > phone: 602.557.6746 │ fax: 602.557.6606 │ email:
>> chad.reid at apollogrp.edu
>> >
>> >
>> > -----Original Message-----
>> > From: Chad Reid
>> > Sent: Sunday, August 04, 2013 7:41 AM
>> > To: 'nanog at nanog.org'
>> > Subject: 204.17.16.0/20 Unreachable via Comcast ASN 7992; Looking for
>> > Help or Contacts
>> >
>> > Hello NANOG,
>> >
>> > A few hundred of our users that use Comcast in the South East United
>> > States (other regions aren't affected) are unable to access our
>> websites in
>> > the IP block 204.17.16.0/20. Based upon testing with the users, they're
>> > getting a destination unreachable from a Comcast backbone router in ASN
>> > 7922:
>> > be-16-pe03.56marietta.ga.ibone.comcast.net [68.86.83.134] reports:
>> > Destination net unreachable.
>> >
>> > We're not a customer of Comcast, nor are any of our ISPs. Because of
>> this,
>> > we can't find anyone at Comcast to look at this issue nor do we have
>> good
>> > contact info to even reach someone. Our users in the South East can open
>> > tickets with Comcast technical support, but you can imagine how
>> successful
>> > they are trying to explain this to frontline support and getting
>> frontline
>> > support to understand.
>> >
>> > Is anyone from Comcast on the list that can assist or know of a contact?
>> >
>> >
>> > Chad M. Reid, Network Administrator II
>> > Work Hours: Sun. - Tue. 6AM-6PM and  Wed. 6AM-3PM (MST -7) Apollo Group
>> |
>> > IT Services │ IT Operations Center (ITOC)
>> > 4025 S. Riverpoint Parkway │ MS: AA-M002 │ Phoenix, AZ 85040
>> > phone: 602.557.6746 │ fax: 602.557.6606 │ email:
>> chad.reid at apollogrp.edu
>> >
>> >
>> >
>> > This message is private and confidential. If you have received it in
>> > error, please notify the sender and remove it from your system.
>> >
>> >
>> >
>> >
>>
>>
>> --
>> Phil Fagan
>> Denver, CO
>> 970-480-7618
>>
>
>

-- 
Phil Fagan
Denver, CO
970-480-7618