Resolver “[error] upstream sent too big header while reading response header from upstream” en NGINX.
Reemplazar en /etc/nginx/fastcgi.conf la configuración por defecto, en mi caso de EasyEngine con servidor web NGINX + fastcgi, los parametros de fastcgi_buffers y fastcgi_buffer_size.
# FastCGI cache settings fastcgi_cache_path /var/run/nginx-cache levels=1:2 keys_zone=WORDPRESS:50m inactive=60m; fastcgi_cache_key "$scheme$request_method$host$request_uri"; fastcgi_cache_use_stale error timeout invalid_header updating http_500 http_503; fastcgi_cache_valid 200 301 302 404 1h; #fastcgi_buffers 16 16k; #fastcgi_buffer_size 32k; fastcgi_buffers 128 4096k; fastcgi_buffer_size 4096k; fastcgi_param SERVER_NAME $http_host; fastcgi_ignore_headers Cache-Control Expires Set-Cookie; fastcgi_keep_conn on;