problemi s nginx reverse proxy & cache_bypass

[seno]

Zdravstvuite, 

Sobral Nginx + purge. Vse zamechatelno rabotajet, cache, purge etc. 
Trebujetsia nekeshirovat faili kotorije naxodiatsia v direktoriji
/analytics/

v konfige :

location ~ /analytics {

                set $do_not_cache 1;
                proxy_no_cache $do_not_cache;
                proxy_cache_bypass $do_not_cache;
                #proxy_cache cache;
                proxy_pass http://backend;
            }

No na vizove http://xxx.com/analytics/file-name.html poluchaju 404.
Reverse proxy obraschajetsia k main serveru, no pochemuto neberet faila
kotorii naxoditsia v nuznoi direktorii. 

Gde iskat konci ?

P.S. izvinite za translit, net russkoi klaviaturi.

-------------------------------------------
nginx version: nginx/0.8.49
built by gcc 4.3.2 (Debian 4.3.2-1.1)
TLS SNI support enabled
configure arguments: --conf-path=/etc/nginx/nginx.conf
--sbin-path=/usr/sbin/nginx --error-log-path=/var/log/nginx/error.log
--pid-path=/var/run/nginx.pid --lock-path=/var/lock/nginx.lock
--http-log-path=/var/log/nginx/access.log
--http-client-body-temp-path=/var/lib/nginx/body
--http-proxy-temp-path=/var/lib/nginx/proxy
--http-fastcgi-temp-path=/var/lib/nginx/fastcgi --with-debug
--with-http_stub_status_module --with-http_flv_module
--with-http_ssl_module --with-http_gzip_static_module --with-ipv6
--with-http_realip_module --with-http_geoip_module
--with-http_xslt_module --with-http_image_filter_module
--with-sha1=/usr/include/openssl --with-md5=/usr/include/openssl
--add-module=/root/nginx-proxy-no-cache/mod_rrd_graph-0.2.0
--add-module=/root/nginx-proxy-no-cache/ngx_http_log_request_speed
--add-module=/root/nginx-proxy-no-cache/agentzh-memc-nginx-module-b2aeae2
--add-module=/root/nginx-proxy-no-cache/ngx_cache_purge-1.1

Posted at Nginx Forum: http://forum.nginx.org/read.php?21,216079,216079#msg-216079