site can't access. - class_core.php on line 317

[muimui]

i get email,

Database error in vBulletin :

mysql_connect(): Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2)
/var/www/vhosts/site.com/forum/includes/class_core.php on line 317

and site down for several time,now its back to normal,after restart my server.
host support says its because apache eror mail function.
why?

[tbworld]

Check your server logs. You did not provide us enough information to assist you.

Apparently your mysql server was down or it quit.

[ozzy47]

I think the connection failed (which happens before the user/password is checked). It could be that the socket (and/or the host name) is wrong, or if it was working before and you haven't changed anything, it may be that the database server isn't running.

It is not a software issue, it is something on your hosts end, so I would contact them.