What would happen if the DNS went down?

[Narnia]

What would happen if the DNS went down (hackers, war, natural disaster, etc)? If I had the ip address of a website, could I still access it? Would websites still work, it would just be very difficult to access webpages or would they stop working?
If typing the ip address of a website would allow me to access it, if I had the ip address of a site like YouTube, would the video suggestions on YouTube still work?
Also, my school is online, how likely is it that it would still work?
Finally, would online videogames like Battlefield 3 (on PC) or star wars battlefront 2 (pc) still work assuming that I had the ip address of a few servers?
Thanks


Article that got me thinking of this: http://www.tomsguide.com/us/Anonymo...DNS-Servers-shut-down-the-web,news-14201.html

Note: I don't actually think that Anonymous can really take down the DNS, I'm just curious as to what would happen if it did go down for some reason.

Edit: would this site still work?

 

[Cutlass]

There are many DNS servers on the net. If the whole system was taken down, the net would be unusable until it was fixed.

 

[warpus]

You'd still be able to connect to websites using their IPs, no?

 

[Narnia]

You'd still be able to connect to websites using their IPs, no?

From the very little bit that I read, it almost sounded like if you typed www.google.com into the search bar you would just get an error message about not being able to find that site. However, if you typed 74.125.224.80 you would still be able to reach google's webpage. Is this right?

 

[Till]

It's pretty much impossible to completely shut down the DNS protocol. What could happen is that important high level servers get disabled (through DDOS or government shenanigans). In that case, parts of the internet would be temporarily unreachable by URL, until a replacement server has been put in place and the missing data has been restored from other servers caches.

Simple websites would still work, and complex multi-domain ones probably too, as they'd have their IP's in their local DNS cache. Google search would be pretty worthless for a while, however.

 

[BandC]

To answer the original question, if the DNS went down totally (very very unlikely) the Internet as you know it would be pretty much useless.

Yes, you could go to websites by typing their web servers' IP addresses but remember that pretty much every URL on those website's web pages still use DNS names so basically you couldn't navigate to any other sites by clicking links. Also, most likely even the website you typed the IP for would not work properly because it wouldn't be able to load the resources (images, JS, CSS) it needs if they depended on absolute domain names.

 

[warpus]

To answer the original question, if the DNS went down totally (very very unlikely) the Internet as you know it would be pretty much useless.

Yes, you could go to websites by typing their web servers' IP addresses but remember that pretty much every URL on those website's web pages still use DNS names so basically you couldn't navigate to any other sites by clicking links. Also, most likely even the website you typed the IP for would not work properly because it wouldn't be able to load the resources (images, JS, CSS) it needs if they depended on absolute domain names.

All the sites I build load all of the required resources using relative paths, so all my sites would work... or at least should, in theory. I use relative paths for most of the links too.

 

[GenMarshall]

Would this be done on a small scale setting in a lab with an isolated mini Internet set up (though it would technically be a intranet)?

 

[innonimatu]

Simple websites would still work, and complex multi-domain ones probably too, as they'd have their IP's in their local DNS cache. Google search would be pretty worthless for a while, however.

No, there would be one problem: host names used directly on the site's code would have to be resolved by the client. The client and its immediate DNS servers might not have those names on cache. But probably not a problem for the major sites.

I would like to seem some more decentralization of DNS. I know that all the root servers are now replicated, but I don't like the very idea of a hierarchical DNS. Handing control over to the ITU or even to national institutions might be the best outcome now, it'd soon spur the use of alternatives. But it's not going to happen soon. And no group (short of one government, perhaps) is going to be able to take the current whole system down. Probably not even the ICANN's management could down all the root servers, as most of the root servers are not actually controlled by their workers. Afaik the software itself is different between several of the servers, so the ISC can't either (through some bug).

 

[CommonKnowledge]

You could always simulate this yourself if you have access to Linux iptables or whatever the Windows equivelant is. DNS uses port 53 so just block outgoing and incoming TCP and UDP packets on that port and see how far you get. Alternatively you could download Wireshark (great program anyway) and analyse the packet stream when connecting to a website and see how much of that is DNS.