
NamePros: Obscure Nginx FastCGI bug uncovered in the aftermath of Duck.com move - nimbosa
https://www.nameprosstatus.com
======
nimbosa
Duck.com domain name transfer hammered NamePros servers so hard that it
singlehandedly uncovered a fairly obscure bug in Nginx's FastCGI caching. It's
gone unnoticed for years, including during rigorous load testing.

Preliminary evidence suggests that fastcgi_cache_key doesn't handle $cookie_*
variables correctly. If the cookie doesn't exist, it seems to result in a
unique key every time. (The workaround was to assign the $cookie_* variable to
another variable and then use that in fastcgi_cache_key.)

If anyone is curious what sort of increase in traffic you should expect from a
link to your site appearing on HN, NamePros is getting about 230 additional
backend requests per second--that doesn't include anything cached by
Cloudflare.

Live Monitor: [https://www.nameprosstatus.com](https://www.nameprosstatus.com)

source:
[https://news.ycombinator.com/item?id=18665292](https://news.ycombinator.com/item?id=18665292)

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zenexer
I appreciate the interest, but this is definitely premature. I still haven't
been able to reproduce it in controlled tests. As I said in the thread to
which you linked, I'll follow up once I've fully investigated.

