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One Broken Router Takes Out Half the Internet?
Silent Stephus writes "I work for a smallish hosting provider, and this morning we experienced a networking event with one of our upstreams. What is interesting about this, is it's being caused by a mis-configured router in Europe — and it appears to be affecting a significant portion of the transit providers across the Internet. In other words, a single mis-configured router is apparently able to cause a DOS for a huge chunk of the Net. And people don't believe me when I tell them all this new-fangled technology is held together by duct-tape and baling wire!"
A couple of Nuclear Subs probably cut an underwater cable...
A router takes out 'half the internet' and I learn this from Slashdot?
Seriously, what is/was the impact? I work for a large e-commerce provider and haven't seen a thing that would indicate a problem today.
My bad. I never should have cut that tape.
Bibo Ergo Sum.
The internet's dirty little secret. It's amazing it works at all.
"I'd rather be a lightning rod than a seismometer." -Ken Kesey
Lucky Yankees with all your fancy technology. If I told you what we use, nobody would respond for fear that in attempting to respond I would cause a few fatalities.
--= Isn't it surprising how badly I spell ?
There is a post in nanog and on isc.sans.org.
AS 47868 causing AS paths to become too long...
http://www.merit.edu/mail.archives/nanog/msg15472.html
And took out THE _WHOLE_ INTERNET!!!!!
It's true! Ask my wife!
"Speaking the Truth in times of universal deceit is a revolutionary act." -- George Orwell
It must have been the "half the Internet" that I don't use. Which would be an interesting half because many of the sites I visit regularly are based in Europe.
From the thread, it looks like AS 47868 was the route being lost.
http://en.wikipedia.org/wiki/Autonomous_System_Number
http://en.wikipedia.org/wiki/Baling_wire
I think you mean baling wire. One uses buckets for bailing.
What is Jen doing with The Internet??
A router takes out 'half the internet' and I learn this from Slashdot?
Non, no, no. You messed up the troll and got modded "Insightful". Let me fix that for you:
A router takes out 'half the internet' and this is front page news at Slashdot? Slow news day?
Thank you, I'll be here all week...
If you want news from today, you have to come back tomorrow.
The AS 47868 decided that they wanted to prepend their ASN about 75 or so times to their BGP announcements. When this got re-populated throughout the rest of the world, a bug in older versions of Cisco IOS still in use on many ISP/NSP networks does not like paths this long. As soon as they saw the prefix with that long of a path, the software terminated the BGP session, resulting in the doorway being closed between the two networks -- So on and so forth throughout the rest of the web.
Make sure you are using cat 5 bailing wire.
-- Terry
In other words, a single mis-configured router is apparently able to cause a DOS for a huge chunk of the Net.
This means the router was able to take out over 9000 internets. Quite impressive.
They need to replace it with a network that is designed to survive a nuclear attack. Oh wait, hang on....
That's the problem. You shouldn't use rouge on your routers.
They think a rouge router is in vouge, but they're out of their leauge. We should haranuge them! A plauge on them! Rip out their tounges so they cannot aruge! Them and their colleauges. Nothing but demagouges and idealouges I say. There can be no dialouge on this matter. Send them to the moruge!
Are you intriuged by my ideas and want to subscribe to my travelouge?
Oh, say does that Star-Spangled Banner entwine / The myrtle of Venus with Bacchus's vine?
This only broke BGP implementations that are getting pretty long in the tooth now, on a moderately recent version of IOS all we saw is:
Feb 17 05:25:03.731 nzdt: %BGP-6-ASPATH: Long AS path 10026 3356 29113 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 47868 received from xxx.xxx.xxx.xxx: More than configured MAXAS-LIMIT
It was definitely an insane path, our routers were configured to drop anything with an AS path longer than 75, old versions of IOS would often just drop the BGP session ( or even crash with some _really_ old versions ).
I'm sure there will be some red faced network engineers updating IOS or even doing forklift upgrades of old boxes at their edges in the near future.
I am a lawyer and this constitutes legal advice and I shall indemnify you against any losses arising from taking it.
This only took down people running fairly old versions of IOS that didn't patch a known bug.
Did not affect non-cisco.
Did not affect modern versions of IOS
Did not affect old versions of IOS that set the knob to limit the max as-path.
You left out 'updating your myspace page', 'writing poetry about how no-one understands' and 'cutting yourself'
Yay me!
A router takes out 'half the internet' and I learn this from Slashdot?
Seriously, what is/was the impact? I work for a large e-commerce provider and haven't seen a thing that would indicate a problem today.
Well I'm not sure about you.
Personally, I have BIGGER news! A single router in a remote rural US state managed to take down the ENTIRE INTERNETS!!!!
Yes, indeed when I noticed my cat had unplugged the power adapter, I replaced it. Then the ENTIRE internet came back! It was amazing how I single-handedly brought back the whole internets. Al Gore would be proud.
If I'm understanding this 'router' thing correctly, its like a faucet connected to the series of tubes?
If not, exactly what role does this router thing play in tube interaction?
Your understanding is rather accurate but what your missing is the manifolds. You see, all the tubes connect to big manifolds with valves to control what gets sent where. At each manifold room there is some poor admin who is in charge of opening and closing valves in order to make sure that the right AOL gets sent down the right tube. In order to keep track of what tube to send your AOL down, the admin keeps a list of all the other manifold rooms and how to get to them. Some of the manifold room operators didn't have a wide enough notebook to write down the new directions so they just closed all of their valves and went home.
Welcome to Sauronet... One Router to Rule them ALL!!!!
Don't worry, it wasn't a DOS attack. That was just the Internet becoming self-aware.
OK, on second thought, maybe worrying is in order.
Yeah, this was my first thought as well. It seems clear that the internet, while designed to route traffic through all sorts of alternate links, is almost certainly being routed through single, centralised listening posts at various intervals.
The last time I experienced a DOS attack it evolved into Windows. Didn't come out of that one unscathed.
They need to replace it with a network that is designed to survive a nuclear attack. Oh wait, hang on....
Wish I had mod points today. Parent should already be SCORE:5 Funny. Apparently not enough Slashdotters know the history/evolution of the net.
If you're referring to the myth that the Internet was "designed to withstand nuclear attack", perhaps Slashdotters know more than you think.
The Internet was designed to allow distributed control, and to withstand telephone company malice and incompetence. This was a much more useful goal than withstanding nuclear attack.
This "article" is incredibly misleading as nothing has really gone awry. It is just another pointless KDAWSON post. These things are getting REALLY old, KDAWSON.
I work for a tier-3 provider, and if "half the Internet" dies, you are going to hear from a half-brained big media outlet (e.g CNN, ABC) VERY fast.
They need to replace it with a network that is designed to survive a nuclear attack. Oh wait, hang on....
Wish I had mod points today. Parent should already be SCORE:5 Funny. Apparently not enough Slashdotters know the history/evolution of the net.
If you're referring to the myth that the Internet was "designed to withstand nuclear attack", perhaps Slashdotters know more than you think.
The Internet was designed to allow distributed control, and to withstand telephone company malice and incompetence. This was a much more useful goal than withstanding nuclear attack.
One of the early arguments made by DARPA folks to politicians, in order to secure continued federal funding for packet switched network development, was the ability of the network to route around failed or destroyed nodes. They made this argument in the context of the cold war, of nuclear war.
It reality, as you state, this argument had little practical impact on the technical development or evolution of the the network. However, it most certainly did have an impact on the commitment of federal/military funding. This is the origin of the "surviving nuclear attack" lore of the development of DARPANET. It's not a myth. It's real.
Take Obama's current stimulus package as a parallel example. It's not going to solve the recession, but it's being sold as such. And the congress bought into it. Just as this stimulus bill isn't what it's being sold as, most likely DARPANET wouldn't have really given us what it was sold as at one point. Nonetheless, it was sold as such, thus creating the lore that you call myth.
Mod the parent up - this is the real cause of the problem.
bgp maxas-limit 75
would stop this on most routers.
One of the early arguments made by DARPA folks to politicians, in order to secure continued federal funding for packet switched network development, was the ability of the network to route around failed or destroyed nodes. They made this argument in the context of the cold war, of nuclear war.
They made that argument in the context of a widely distributed POTS copper wire network.
The infrastructure of today's internet is fiber based.
And most of that fiber is consolidated in a small number of long backhaul runs.
Remember that grad student whose thesis was classified because he gathered up public documents and mapped out the fiber runs that make up the domestic internet? They classified it (and pulled most of the references he used) because his analysis showed there were a few critical points which, if disrupted, would effectively fracture the domestic internet infrastructure.
The internet isn't nearly as bulletproof as the DoD would like and there isn't much they can do about it short of laying new fiber that skips over the vulnerable points.
[Fuck Beta]
o0t!
Aw heck, someone in Nebraska is going to trip over one power cord, and shut down the Interweb. :)
In addition to using public maps, I did a lot more research. I had my own little project going for a little while. The project was intended to monitor for faults between datacenters we had equipment in. I added the root nameservers. I also had a few other points, such as friends houses and places they had virtual hostings at.
Simply enough, it was running traceroutes from everywhere I had control to all points in my "network". I stored what router attached to each hop in a database.
I located each hop simply by the city it was located in. Some were easy. Some weren't so easy.
It was fun and games with 100 routers. I was manually setting city and state locations.
It was a little less fun when it grew to 500 routers. I wrote regular expressions to take known naming conventions and make them into city names. That sounds easy, but it gets pretty hard pretty quick.
It was a lot less fun when the list grew to several thousand routers.
Basically, ever time there was a routing change, I found new routers.
I had a lot of fun using both Google Maps to show the routes (for routers that I could place in a city), and a Graphviz model of the Internet as we observed it. It was a very big map. That was only what we had observed. I doubt we even saw a very small percentage (probably less than 0.01%) of the routes.
The map got very very very complicated. I could point out choke points. They existed, but there were also alternative routes.
Hell, even on a single good provider, there are no good choke points. On one Tier 1 provider that I used, in a non-core city, they had 6 diverse routes with OC192's. It wasn't a matter of me trusting them when they told me. I saw the routes showing up.
There are 4 cities in the US, where if say a big nuke hit each one, ya, the Internet would be hurting. You may not get from Provider A to Provider B, but you'd still have some connectivity within your own provider, and other peerings would start working fairly quickly. More obviously, you'd find that some sites that are hosted in one city would be inaccessible. That's why geographic and topological diversity is very important for anyone who wants to keep their stuff up and running.
Google puts stuff out all over the place for a reason. If a route, or a dozen routes, go funky, you'll very likely still be able to reach some datacenter.
My office is connected by 3 uplinks. They're all with different providers. The odds of a provider outage killing the office is pretty slim. Other things can happen though. Lightning hit a transformer across the street, which serviced our building. From what people on that side of the building said, it was very pretty. :) Was our Internet connection dead? No. Well, not totally. We still had 2 uplinks working. We didn't have power for the desktops though. The UPS (a big one, not the little desktop ones) provides for the server room and a very few workstations.
The biggest effect we saw from that outage was that cell phone service became minimal. The top of our building is also used for cell phone coverage. Without those antennas working, we only had service from the surrounding towers. It probably didn't help that there was now an office building full of people who were evacuated to the ground floor (it tripped the fire alarm), so almost everyone were on their cell phones making calls to customers, friends, family, etc.
The most upset people were stuck in the elevator. They were already going downstairs for a smoke break, when it got stuck because those aren't backed up with anything at all.
Serious? Seriousness is well above my pay grade.