nginx serving wrong website under proxy_cache

[Igor Sysoev]

On Sun, May 03, 2009 at 02:05:57AM -0400, Jim Ohlstein wrote:

> 
> 
> Igor Sysoev wrote:
> >On Sun, May 03, 2009 at 01:18:30AM -0400, Jim Ohlstein wrote:
> >
> >  
> >>Igor Sysoev wrote:
> >>    
> >>>On Sat, May 02, 2009 at 11:16:47PM -0400, Jim Ohlstein wrote:
> >>>
> >>> 
> >>>      
> >>>>Correction:
> >>>>
> >>>>The question should read:
> >>>>
> >>>>Do I need to use two fastcgi_cache_key settings if a site serves both 
> >>>>http and https?
> >>>>   
> >>>>        
> >>>If you use the same backend - no:
> >>>
> >>>     server {
> >>>         listen 80;
> >>>         location / {
> >>>             fastcgi_pass       backend:9000;
> >>>             fastcgi_cache_key  backend:9000$request_uri;
> >>>         }
> >>>     }
> >>>
> >>>     server {
> >>>         listen 443;
> >>>         location / {
> >>>             fastcgi_pass       backend:9000;
> >>>             fastcgi_cache_key  backend:9000$request_uri;
> >>>         }
> >>>     }
> >>>
> >>> 
> >>>      
> >>I am using the same backend and configured like this:
> >>
> >>server {
> >>   listen  80;
> >>
> >>   location / {
> >>       fastcgi_pass backend;
> >>       fastcgi_cache one;
> >>       fastcgi_cache_key backend$request_uri;
> >>   }
> >>}
> >>
> >>server {
> >>   listen     443;
> >>   location / {
> >>       fastcgi_pass backend;
> >>       fastcgi_cache one;
> >>       fastcgi_cache_key backend$request_uri;
> >>   }
> >>}
> >>    
> >
> >Yes, this is OK.
> >
> >  
> >>For what it may be worth, I have seen some md5 collisions in the error 
> >>log:
> >>
> >>2009/05/03 00:39:18 [crit] 21997#0: *61 cache file 
> >>"/usr/local/nginx/cache/0/da/90e8de013d4126fbab247d12350fdda0" has md5 
> >>collision, client: my.ip.addr.ess, server: mydomain.com, request: "GET 
> >>/rtwhtrsyrn/010110A/687474702s7777772r777732746s7073697465732r636s6q2s627574746s6r2r7068703s753q776s726p6477617274776s7n6s6r655s636s6q 
> >>HTTP/1.1", host: "mydomain.com", referrer: 
> >>"https://mydomain.com/rtwhtrsyrn/010110A/687474702s776s726p6477617274776s7n6s6r652r636s6q2s666s72756q732s616r6r6s756r63656q656r74732s31333535392q6r6s2q796s752q6172656r742q6372617n792r68746q6p"
> >>2009/05/03 00:39:24 [crit] 21997#0: *44 cache file 
> >>"/usr/local/nginx/cache/0/da/90e8de013d4126fbab247d12350fdda0" has md5 
> >>collision, client: my.ip.addr.ess, server: mydomain.com, request: "GET 
> >>/rtwhtrsyrn/010110A/687474702s7777772r777732746s7073697465732r636s6q2s627574746s6r2r7068703s753q776s726p6477617274776s7n6s6r655s636s6q 
> >>HTTP/1.1", host: "mydomain.com", referrer: 
> >>"https://mydomain.com/rtwhtrsyrn/010110A/687474702s776s726p6477617274776s7n6s6r652r636s6q2s666s72756q732s2r2r2s"
> >>    
> >
> >nginx uses md5 create a cache key and use the key as path to a cache file,
> >90e8de013d4126fbab247d12350fdda0 in you case. Besides, in the file there
> >is crc32 of the original key to test possible md5 collisions.
> >
> >Could you run
> >
> >head -1 /usr/local/nginx/cache/0/da/90e8de013d4126fbab247d12350fdda0 | 
> >hexdump
> >head -2 /usr/local/nginx/cache/0/da/90e8de013d4126fbab247d12350fdda0 | 
> >tail -1
> >
> >?
> >
> >
> >  
> 
> [root at saturn logs]# head -1 
> /usr/local/nginx/cache/0/da/90e8de013d4126fbab247d12350fdda0 | hexdump
> 0000000 8ab0 1afc 0000 0000 1a20 b835 0032 0000
> 0000010 0000 0000 0000 0000 0000 0000 0000 0000
> 0000020 028b 0000 0000 0000 000a              
> 0000029
> [root at saturn logs]# head -2 
> /usr/local/nginx/cache/0/da/90e8de013d4126fbab247d12350fdda0 | tail -1
> KEY: 
> unix:/tmp/cgi.sock.1:/rtwhtrsyrn/010110A/687474702s7777772r777732746s7073697465732r636s6q2s627574746s6r2r7068703s753q776s726p6477617274776s7n6s6r655s636s6q

It's seems like nginx bug. Could you create debug log ?


-- 
Igor Sysoev
http://sysoev.ru/en/