[Concrete CMS] nginx conf to run Concrete CMS on subdirectory

server_append_subdirectory.conf

location ^~ /sub {
    ## Try to find a file with given URL, if not pass to Concrete
    try_files $uri $uri/ /sub/index.php?$query_string;

    location ~ \.php$ {
        include /etc/nginx/fastcgi.conf;
        fastcgi_split_path_info ^(/sub)(/.*)$;
        fastcgi_param SCRIPT_NAME /sub/index.php;
        fastcgi_param SCRIPT_FILENAME $realpath_root/sub/index.php;
        fastcgi_param PATH_INFO $fastcgi_path_info;
        fastcgi_pass ${NGINX_FASTCGI_PASS:-php}:9000;
    }
}