If you’ve accidentally deleted the debian-sys-maint user, you can easily re-create the user.
The password is stored in /etc/mysql/debian.cnf:
# Automatically generated for Debian scripts. DO NOT TOUCH!
[client]
host = localhost
user = debian-sys-maint
password = TOP-SECRET
socket = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
host = localhost
user = debian-sys-maint
password = TOP-SECRET
socket = /var/run/mysqld/mysqld.sock
basedir = /usr
To re-create the user, login as root-user into mysql and run the following query:
INSERT INTO `mysql`.`user` (
`Host`,
`User`,
`Password`,
`Select_priv`,
`Insert_priv`,
`Update_priv`,
`Delete_priv`,
`Create_priv`,
`Drop_priv`,
`Reload_priv`,
`Shutdown_priv`,
`Process_priv`,
`File_priv`,
`Grant_priv`,
`References_priv`,
`Index_priv`,
`Alter_priv`,
`Show_db_priv`,
`Super_priv`,
`Create_tmp_table_priv`,
`Lock_tables_priv`,
`Execute_priv`,
`Repl_slave_priv`,
`Repl_client_priv`,
`Create_view_priv`,
`Show_view_priv`,
`Create_routine_priv`,
`Alter_routine_priv`,
`Create_user_priv`,
`ssl_type`,
`ssl_cipher`,
`x509_issuer`,
`x509_subject`,
`max_questions`,
`max_updates`,
`max_connections`,
`max_user_connections`
)
VALUES (
'localhost',
'debian-sys-maint',
password('TOP-SECRET'),
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'Y',
'N',
'N',
'N',
'N',
'N',
'',
'',
'',
'',
0,
0,
0,
0
);
FLUSH PRIVILEGES;