[146343] in North American Network Operators' Group
Re: Anyone seen this kind of problem? SIP traffic not getting to
daemon@ATHENA.MIT.EDU (Sean Harlow)
Wed Nov 9 14:01:07 2011
From: Sean Harlow <sean@seanharlow.info>
In-Reply-To: <CADs2+OE2VDVE_RaGE5R+=obYguHj0s8v4LokOhv7Bu0ayEbwXg@mail.gmail.com>
Date: Wed, 9 Nov 2011 13:59:56 -0500
To: Jay Nakamura <zeusdadog@gmail.com>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
I can't say I have a specific answer to your question, but yesterday I =
was seeing major packet loss on outbound audio from all my VoIP =
customers using Qwest and going in to servers on L3. It's entirely =
possible that SIP was also being lost, just the audio was the more =
notable and pressing issue. It seems to be resolved at this point, but =
we have not yet heard from Qwest what the actual problem was.
This was with sites in Northeast Ohio and the Chicago area connecting to =
servers in New York and LA for what it's worth.
----------
Sean Harlow
sean@seanharlow.info
On Nov 9, 2011, at 1:47 PM, Jay Nakamura wrote:
> We ran into a strange situation yesterday that I am still trying to
> figure out. We have many VoIP customers but yesterday suddenly select
> few of them couldn't reach the SIP provider's network from our
> network.
>=20
> I could traceroute to the SIP providers server from the affected
> clients' IP just fine. I confirmed that the SIP traffic was leaving
> our network out the interface to the upstream provider and the SIP
> provider says they couldn't see the SIP traffic come into their border
> router.
>=20
> SIP traffic coming from SIP provider to the affected customer came
> through fine. It's just Us -> SIP server was a problem.
>=20
> I thought there may be some strange BGP issue going on but we had
> other customers within the same /24 as the affected customers and they
> were connecting fine.
>=20
> The traffic at the time traversed
>=20
> Our network -> Qwest/century link -> Level 3 -> SIP provider
>=20
> I changed the routing around so it would go through our other
> upstream, AT&T, and it started working. With AT&T, the route was
>=20
> Our network -> AT&T -> Level 3 -> SIP provider
>=20
> So my questions is, is it possible there is some kind of filter at
> Qwest or Level 3 that is dropping traffic only for udp 5060 for select
> few IPs? That's the only explanation I can come up with other than
> the whole Juniper BGP issue 2 days ago left something in between in a
> strange state? I read the post about XO doing filtering on transit
> traffic, I haven't seen anyone say Level 3 or Qwest is doing the same.
>=20
