xn-- on domain, what it means?

Its the result of IDNA encoding; i.e. converting your unicode domain name to its ASCII equivalent which has to be done as DNS is not unicode-aware. The xn-- says “everything that follows is encoded-unicode”.

htaccess redirect all pages to single page

If your aim is to redirect all pages to a single maintenance page (as the title could suggest also this), then use: RewriteEngine on RewriteCond %{REQUEST_URI} !/maintenance.php$ RewriteCond %{REMOTE_HOST} !^000\.000\.000\.000 RewriteRule $ /maintenance.php [R=302,L] Where 000 000 000 000 should be replaced by your ip adress. Source: http://www.techiecorner.com/97/redirect-to-maintenance-page-during-upgrade-using-htaccess/