While I was running some scripts, of my new project, from time to time the PHP kinda had some breaks…. went to error.log and I saw the following error.

2015/08/02 19:42:19 [error] 25586#0: *8735692 upstream sent too big header while reading response header from upstream, client: 84.91.69.69, server: www.flow.domain.com, request: "GET /worker/?action=runHTTP/1.1", upstream: "fastcgi://unix:/var/run/php5-fpm.sock:", host: "flow.domain.com", referrer: "http://flow.domain.com/worker/?action=flushall"

I had to edit my nginx domain.conf and add the lines in bold!

location ~ \.php$ {
 try_files $uri =404;
 fastcgi_split_path_info ^(.+\.php)(.*)$;
 fastcgi_pass unix:/var/run/php5-fpm.sock;
 fastcgi_index index.php;
 include fastcgi_params;
 fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name;
 access_log off;
 fastcgi_buffers 16 16k;
 fastcgi_buffer_size 32k;
}

OK!
Save it and restart nginx!
Should solve it! 🙂