[146345] in North American Network Operators' Group
RE: Anyone seen this kind of problem? SIP traffic not getting to
daemon@ATHENA.MIT.EDU (Preston Parcell)
Wed Nov 9 14:05:10 2011
From: Preston Parcell <preston.parcell@viawest.com>
To: Sean Harlow <sean@seanharlow.info>, Jay Nakamura <zeusdadog@gmail.com>
Date: Wed, 9 Nov 2011 11:04:01 -0800
In-Reply-To: <1A009F7C-6D9C-4CD4-9206-3027D4ADEB70@seanharlow.info>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
What was the timeframe for your issues? Just curious since we saw some stra=
ngeness last night.
Preston=20
-----Original Message-----
From: Sean Harlow [mailto:sean@seanharlow.info]=20
Sent: Wednesday, November 09, 2011 12:00 PM
To: Jay Nakamura
Cc: NANOG
Subject: Re: Anyone seen this kind of problem? SIP traffic not getting to d=
estination but traceroute does
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. I=
t 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 se=
rvers 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=20
> figure out. We have many VoIP customers but yesterday suddenly select=20
> few of them couldn't reach the SIP provider's network from our=20
> network.
>=20
> I could traceroute to the SIP providers server from the affected=20
> clients' IP just fine. I confirmed that the SIP traffic was leaving=20
> our network out the interface to the upstream provider and the SIP=20
> provider says they couldn't see the SIP traffic come into their border=20
> router.
>=20
> SIP traffic coming from SIP provider to the affected customer came=20
> 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=20
> other customers within the same /24 as the affected customers and they=20
> 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=20
> 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=20
> Qwest or Level 3 that is dropping traffic only for udp 5060 for select=20
> few IPs? That's the only explanation I can come up with other than=20
> the whole Juniper BGP issue 2 days ago left something in between in a=20
> strange state? I read the post about XO doing filtering on transit=20
> traffic, I haven't seen anyone say Level 3 or Qwest is doing the same.
>=20
