[nginx] Is proxy_cache_valid required?

[Robert Paprocki]

Hello!

I had trouble this morning setting up a basic cache with a proxy. Based
on the proxy documentation and
http://nginx.com/resources/admin-guide/caching/, I did not expect to
have to set proxy_cache_valid; however, when this directive was not set
anywhere, I saw no cache files written.

My config file is as below:

worker_processes  1;
user freewaf freewaf;
error_log logs/error.log debug;
worker_rlimit_core  500M;
working_directory   /tmp;

events {
    worker_connections 1024;
}

http {
	lua_package_path '/usr/local/openresty/lualib/fw/?.lua;;';
	lua_shared_dict fw_shm 50m;
	lua_regex_match_limit	100000000;

	client_body_buffer_size 512k;
	client_max_body_size 2m;
	proxy_http_version 1.1;

	proxy_cache_path /fw/shm/cache levels=1:2 keys_zone=fw:32m;

	include conf.d/*.conf;
}

upstream upstream_2 {
	server 23.226.226.175     ;
}

server {
	server_name cryptobells.com www.cryptobells.com;
	access_log logs/cryptobells.com.access.log;
	error_log logs/cryptobells.com.error.log;
	client_max_body_size 2m;
	listen 80;
	proxy_cache fw;
	proxy_cache_valid 200 302 60m;
	proxy_cache_valid 404 1m;

	location / {
		default_type text/html;
		proxy_set_header Host $host;
		proxy_set_header X-Forwarded-For $remote_addr;
		proxy_pass http://upstream_2;
	}

	location ~* \.(jpg|jpeg|gif|png|css|js|ico|xml)$ {
		expires 1d;
		proxy_set_header Host $host;
		proxy_set_header X-Forwarded-For $remote_addr;
		proxy_pass http://upstream_2;
	}
}




However, with the following commented out:

proxy_cache_valid 200 302 60m;
proxy_cache_valid 404 1m;

No caching content was written. Debug logs don't show anything out of
the ordinary (though I will post if you like); any thoughts on this?