- Test - lists.nanog.org

Re: iPhone and Network Disruptions ...
by Prof. Robert Mathews (OSIA) 26 Jul '07

26 Jul '07

Hank, Warren, & Fellow Nanogers: Looking at this issue with an *'interoperability lens,'* I remain puzzled by a personal observation that at least in the publicized case of Duke University's Wi-Fi net being effected, the "ARP storms" did not negatively impact network operations UNTIL the presence of iPhones on campus. The nagging point in my mind therefore, is: why have other Wi-Fi devices (laptops, HPCs/PDAs, Smartphones etc.,) NOT caused the 'type' of ARP flooding, which was made visible in Duke's Wi-Fi environment? Why did this issue become MOST prominent with the introduction of Apple's iPhone on campus? In that sense, my *original question* regarding iPhone's 'unique' operational circumstance(s) will have/need to be considered. Initial analysis tells me that we may not be far into that aspect but, we might need to... Again, I wish to thank you for the responses. All my best, Robert. --

7 6

Cogent issues in Chicago?
by Brandon Galbraith 26 Jul '07

26 Jul '07

Anyone experiencing issues with their Cogent connectivity right now? -brandon

1 0

San Francisco Power Outage
by Jonathan Lassoff 26 Jul '07

26 Jul '07

Just a heads up to anyone on list that PG&E has just sustained a large outage in San Francisco that has caused a few hiccups (both network, electrical, infrastructural, etc.) around the city. I've confirmed that both customers in 365 Main and parts of telecom 1 have both sustained brief blackouts. No word yet form 200 Paul. Anyone in the area that could use a hand with anything, I'll probably be wrapping up fixes for my stuff soon, and would be glad to help however I can. Cheers, jonathan -- Jonathan Lassoff echo thejof | sed 's/^/jof(a)/;s/$/.com/' http://thejof.com 415-215-2464 GPG: 0xC8579EE5

20 26

Call for Volunteers for NANOG Mailing List Committee
by Joe Abley 26 Jul '07

26 Jul '07

People of NANOG, Members of the Mailing List Committee come from a variety of technical and organisational backgrounds, but share a desire to help the NANOG list function as an effective resource for network operators. The Steering Committee, in consultation with the current Mailing List Committee, are interested in hearing from people who are interested in joining the team, volunteering their time and energy to help make the NANOG list better. We are looking for people who care about the NANOG list, who are habitual e-mail addicts, and who have a thorough understanding of NANOG culture. If this sounds like you, we would encourage you to put your name forward. To volunteer, send a note to steering(a)nanog.org containing a brief summary of how you think the NANOG list could be better, and how you think you could help make a difference. We'll consider every response we get before 4 August 2007. Thanks for your time, Joe Abley, for the NANOG SC Alex Pilosov, for the NANOG MLC

1 0

Re: Why do we use facilities with EPO's?
by George William Herbert 25 Jul '07

25 Jul '07

>If they can be avoided, why do we put up with them? Major electrical fire, or arcing in the datacenter. Flood in the datacenter. Accidental water sprinkler discharge in the datacenter. Equipment fire that the FM-200 didn't put out, and you want not to have the sprinklers go off if you can avoid it. Equipment fire in a room without FM-200 in the first place. Equipment fire with sprinkler discharge, and you'd really rather just dry out the equipment than have to replace it all. Electrical worker who's electrocuted himself and going to die if you can't make the power go away. There are a very few exceptions, but for our practical purposes, people really ought to simply go to multiple site redundancy rather than thinking about bending major safety assumptions in how we operate individual buildings. You may have a few less outages, but you may also kill someone. What the Navy does on ships, for critical ship safety and combat systems; what the FAA does for their radar facilities and air traffic control facilities; what Telcos do, these are different operating regimes, and there are associated higher risk acceptance with the different equipment setups and safety procedures. -george william herbert gherbert(a)retro.com

2 1

An Internet IPv6 Transition Plan
by John Curran 25 Jul '07

25 Jul '07

Folks - There's quite a few IPv6 transition technologies, each with its own camp of supporters based on particular world view of the hardest & easiest system elements to change. One of the challenges this poses is that it's very easy to get caught up in the various transition approaches and miss the high-level view of what needs to be accomplished. In an effort to communicate one possible transition plan in a technology agnostic manner, I've written an Internet draft which highlights the expectations that organizations could face over the next few years: http://www.ietf.org/internet-drafts/draft-jcurran-v6transitionplan-00.txt I'd be interested in hearing any and all feedback from the NANOG community on this draft; feel free to send such privately if you'd prefer a degree of anonymity, or have the urge to use language inappropriate in public... ;-) Thanks! /John

7 11

Re: Why do we use facilities with EPO's?
by George William Herbert 25 Jul '07

25 Jul '07

>I've always wondered who died or was injured and caused the EPO to >come in to existence. There have been lots of "EPO caused downtime" >stories, but does anyone on the NANOG list even have one single >"Thank God for the EPO" story? I'll feel better about the general >state of the world if I know that the EPO actually has a real valid >use that has been ACTUALLY PROVEN IN PRACTICE rather than just in >someone's mind. > > >-Jerry <----Is so anti EPO, he has no remote EPO buttons, and even >has the irrational fear about the jumper on the "EPO terminal strip" >inside his UPSes coming undone. A friend of mine is a volunteer firefighter (and ex-ISP CEO, used to be on the list). I'm not sure that he'd voluntarily enter a burning datacenter to put it out if there wasn't an EPO. Firefighters won't use water on live electrical fires. If your response plan to a fire in the datacenter is "the building burns down and hope nobody's inside it still" then you're set. I've seen someone electrocuted and frozen on the wire in a non-datacenter setting; we flipped the building breaker, which was further than an EPO would have been. It wasn't through his chest, and was only 110 V, so it probably didn't make a difference that it took a minute to turn it off instead of 10 seconds. There were no severe burns, etc. I've seen equipment catch on fire in a datacenter. If I hadn't been able to cut off the power locally, the EPO was the last line of defense... People I know have hit the EPO when sprinklers discharged in the datacenter. If you're lucky these won't happen to you. But that's not why safety rules are put in place. Unluck happens. -george william herbert gherbert(a)retro.com

1 0

Re: San Francisco Power Outage
by George William Herbert 25 Jul '07

25 Jul '07

Michael Dillon writes: >> And the stories that the power guy I'm working with tells >> about foreign facilities, particularly in middle east war >> zones, are really scary... > >> We fundamentally do not have the facilities problem >> completely nailed down to the point that things will never >> drop. Level 4 >> datacenters can, and will, fail. Nothing you can do including >> just doing 48V DC for everything are truly foolproof solutions. > >A single level 4 datacenter is a Single Point of Failure! > >Two of those middle-eastern style facilities is... ? >Has anyone actually kept track of all these data center failures over >the years and done some statistical analysis on it? Maybe two half-baked >data centers is better than one over the long run? > >Remember that one 10-12 years ago in (Palo Alto, Mountainview?) where a >lady in a car caused a backhoe driver to move out of the way which >resulted in him cutting a gas line which resulted in the fire department >evacuating the data center, cutting off electricity in the area, and >forbidding the diesel generators to be switched on? Santa Clara. I was working right outside the evacuation radius. Which exchange point was in the building? PB-NAP? CIX? I remember we had a net-dark event associated, but not which one. It was a bad day... The lesson, as you point out, is that geographical redundancy is sometimes necessary. This is as true for providers as for datacenter end-users... -george william herbert gherbert(a)retro.com

1 0

Re: Why do we use facilities with EPO's?
by Warren Kumari 25 Jul '07

25 Jul '07

On Jul 25, 2007, at 3:35 PM, Patrick W. Gilmore wrote: > > On Jul 25, 2007, at 2:03 PM, Tuc at T-B-O-H.NET wrote: > >>> If they can be avoided, why do we put up with them? Do we really >>> want our colo in downtown San Francisco bad enough to take the risk >>> of having a single point of failure? How can we, as engineers, ask >>> questions about how many generators, how much fuel, and yet take >>> for granted that there is one button on the wall that makes it all >>> turn off? Is it simply that having colo in the middle of the city >>> is so convenient that it overrides the increased cost and the >>> reduced >>> redundancy that are necessitated by that location? >>> >> You forgot the default "Single Point of Failure" in anything.. >> >> HUMANS. > > The earth is a SPoF. Let's put DCs on the moon. > > Besides, safety always overrides convenience. And I don't think > that is a bad trade off. Me neither... Having multiple redundant sites (and a well designed network between them) is almost always going to be better than a single, wildly redundant site. No matter how much redundancy you build into a single site, you cannot (realistically) engineer away things like floods, etc. Planning your redundancy and testing it though is very important... Random anecdote (from a friend, I don't know if it true or not): Back in the day (before cheap international circuits), a very large financial in New York needed connectivity to some branches in Europe, so they bought some capacity on a satellite transponder and built their own ground-station (not cheap) fairly close to NY. They then realized that the needed a redundant ground station in case the first one failed or something similar, so the built a second ground- station, just outside Jersey City.... One of the satellite connectivity failure modes is... rain fade..... W > > -- > TTFN, > patrick > > -- "Does Emacs have the Buddha nature? Why not? It has bloody well everything else!"

1 0

Re: 365 Main - an operators' nightmare?
by Jim Popovitch 25 Jul '07

25 Jul '07

On Tue, 2007-07-24 at 19:26 -0700, Rusty Hodge wrote: > > Think that's good? It gets better.... > > > > http://valleywag.com/tech/breaking/angry-mob-gathers-outside-sf- > > datacenter-282053.php > > That article states that only Colo 4 was affected. > > I'm in Colo 7 and it was affected as well. > > You're not seriously believing the disgruntled employee story are you? No. ;-) But it is otherwise believable. I've seen people hit big-red-buttons in disbelief before, doing so in anger seems very plausible. -Jim p.

4 3