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Why Browsers Blamed DNS For Facebook Outage
Julie188 writes "That was probably the only time 'DNS' will ever be a trending term on Twitter. The cause was Facebook's 2.5 hour outage on Thursday, which incorrectly told users trying to access the site that a DNS error was to blame. In truth, experts who've read Facebook's explanation say the site went down because Facebook gave itself a distributed denial-of-service attack when a system admin misconfigured a database. So why was DNS blamed? The 27-year-old communications protocol has been known to cause other, somewhat similar outages."
The 27-year-old communications protocol
So? TCP/IP is 36 years old.
http://rs79.vrx.net/works/photoblog/2010/Sep/23/
Notice the page, being served from facebook.com, saying "bad DNS". Think about that
for a second.
Need Mercedes parts ?
The confusion might have come from the fact that when I looked, there seemed to also be some DNS problem.
Basically, when asking directly, the servers that are authoritative for the zone were giving me a CNAME for the 'ANY' query, but not the associated A records, which it should, since the CNAME was pointing to a host name within the same authority. At this point, any sensible resolver stops asking !
This only lasted for a little while though - so it might have been a glitch or possibly a deliberate action related to how they were trying to fix the underlying issue itself - possibly averting traffic until they actually solved the actual problem.
--Ivan
It didn't fail, they turned it off. This was the easiest way to "shut off the entire site" as their post-mortem describes. The DNS errors users saw were being generated by the front-end HTTP proxies, not by client browsers, which caused most of this confusion. Once the database issue cleared, they reactivated the DNS entries for the back-end servers one cluster at a time and the site came back.
You won't find it on the home page. It was a post by a developer on the dev blog. He later removed it and apparently moved it to his personal blog.
Palestine Written by Clem on Sunday, May 3rd, 2009 @ 12:34 am | Main Topics
This is not the place to talk about this but I am deeply touched by what is happening over there. I feel disgust and guilt with us passively witnessing it and our money and weapons supporting it. I don't want to use my name or this project to push my own ideas about this but I spend a lot of time working and giving away, sharing and receiving to and from a lot of people.
I'm only going to ask for one thing here. If you do not agree I kindly ask you not to use Linux Mint and not to donate money to it.
I hope for these people to be able to live decently in the future and for me not to have anything to do with the misery they're in at the moment.
I promise not to talk about this anymore. I don't want any money or help coming from Israel or people who support the action of their current government.
Thank you for your understanding. This is very important to me.
It is the most used website in the world (more userhours/month spent of Facebook than any other site), the fastest growing internet community (when measured in new users/month), etc... And as such it is an engineering masterpiece (in software engineering and probably in several other areas, too). When it goes down for several hours, it is a newsworthy event.
For us who work for advertising agencies, FB downtime is also a financially notable event.