connect() to unix:/var/run/php5-fpm.sock failed (11: Resource temporarily unavailable) while connect

vi /etc/php5/fpm/pool.d/www.conf

In your fastcgi conf change:

fastcgi_pass unix:/var/run/php5-fpm.sock;

to:

fastcgi_pass 127.0.0.1:9000;

And do the same on Nginx configuration file:

nano -w /etc/nginx/conf.d/site.com.conf

Set the fastcgi_pass variable to use the 9000 port we specified at php-fpm before:

fastcgi_pass 127.0.0.1:9000;