Ater rebooting a memcache node, I am getting an error on root blog only, with a telling error log message from wp-includes/ms-settings.php.
[Thu Jul 07 18:55:27 2011] [error] [client 184.108.40.206] PHP Warning: Attempt to assign property of non-object in /var/www/domain.php/wp-includes/ms-settings.php on line 114
Dumping the $current_blog var from that file shows there's no site data loaded into the object, just a couple plugin references, which is why lines like these are failing:
$blog_id = $current_blog->blog_id; $public = $current_blog->public;
How can I clear site options in memcache by hand? What are the keys?