error: 'Access denied for user 'debian-sys-maint'@'localhost' (using password: YES)'
That’s because Debian has a MySQL account debian-sys-maint used for switching on/off and checking status. The password for that user should be the same as stored in /etc/mysql/debian.cnf. The file looks like this:
# Automatically generated for Debian scripts. DO NOT TOUCH! [client] host = localhost user = debian-sys-maint password = <password> socket = /var/run/mysqld/mysqld.sock [mysql_upgrade] host = localhost user = debian-sys-maint password = <password> socket = /var/run/mysqld/mysqld.sock basedir = /usr
If the password doesn't match (for example because you changed it manually) the init script won't work anymore. You should set the password according to the file. So
mysql -u root -p # Then type MySQL root password GRANT ALL PRIVILEGES ON *.* TO 'debian-sys-maint'@'localhost' IDENTIFIED BY '<password>';
innobackupex: Error: Original data directory '/var/lib/mysql' is not empty!