Welcome to Geeklog Wednesday, May 22 2013 @ 10:19 AM EDT
When clicking on the database backup link from the Admin menu, the following command is issued.
/usr/bin/mysqldump -hlocalhost -udbuser -pdbpassword -Q
localhost, dbuser, dbpassword and -Q are derived from your config.php
$_DB_host = 'localhost';
$_DB_user = 'dbuser';
$_DB_pass = 'dbpasssword';
$_CONF['mysqldump_options'] = '-Q';
So in your instance you would change those arguments to what your config.php says. The host is probably still localhost, but your dbuser and dbpassword will be different.
Also the command /usr/bin/mysqldump is derived from config.php. $_DB_mysqldump_path = '/usr/bin/mysqldump';
If you have phpMyAdmin with your server you can do a manual backup.
For an automatic solution using a cronjob, see this story: Backing Up Geeklog. This is also what we're using to backup the geeklog.net database.
mysqldump is an external application and on some setups, it's not possible to execute external applications from PHP scripts, e.g. when
safe_mode=on, when open basedir restrictions are in effect and the path where mysqldump is located is not one of the allowed paths, or when your hosting service has disabled the PHP
All of the above are server-side settings, so try asking your hosting service for help (or change them yourself if it's your own server).