I tried to set up nginx as a front end cache for my WMS server. The typical WMS request is:
http://localhost:8080/geoserver/somestring/wms?version=1.1.1&service=WMS&request=WMS&....
Below is my nginx configuration:

/etc/nginx/nginx.conf:
user vriuser;
worker_processes 4;
pid /var/run/nginx.pid;

events {
worker_connections 768;
# multi_accept on;
}

http {
sendfile on;
tcp_nopush on;
tcp_nodelay on;
keepalive_timeout 65;
types_hash_max_size 2048;

include /etc/nginx/mime.types;
default_type application/octet-stream;

access_log /var/log/nginx/access.log;
error_log /var/log/nginx/error.log;

proxy_buffering on;
proxy_cache_valid any 10m;
proxy_cache_path /var/geoserver/cache levels=1:2 keys_zone=one:10m inactive=7d max_size=5000m;
proxy_temp_path /var/geoserver/cache/tmp;

gzip on;
gzip_disable "msie6";

# gzip_vary on;
gzip on;
gzip_disable "msie6";

include /etc/nginx/conf.d/*.conf;
include /etc/nginx/sites-enabled/*;
}

/etc/nginx/sites-enabled/geoserver.conf
server {
listen 80;
#server_name localhost;
root /home/geoserver/webapps/geoserver;

location /geoserver {
proxy_pass http://localhost:8080;
proxy_cache one;
proxy_cache_key backend$request_uri;
proxy_cache_valid 200 5h;
proxy_cache_use_stale error timeout invalid_header;
}
}

Both nginx and my WMS servers were running without errror. However, when I inspect the /var/geoserver/cache directory, I did not see anything file in there. Does it mean my configuration is not correct? How do I know if nginx caches my WMS responses? Any help on this is greatly appreciated.

Many thanks in advance.

Regards,
Tam