Issue

You get the following errors from your server after running schedule logrotate tasks

/etc/cron.daily/logrotate:
mysqladmin: connect to server at 'localhost' failed
error: 'Access denied for user 'root'@'localhost' (using password: NO)'
error: error running shared postrotate script for '/var/log/mysql/mysql.log /var/log/mysql/mysql-slow.log /var/log/mysql/mariadb-slow.log /var/log/mysql/error.log '
run-parts: /etc/cron.daily/logrotate exited with return code 1

You get this error when running the command in ssh

mysqladmin --defaults-file=/etc/mysql/debian.cnf --local flush-error-log
mysqladmin: connect to server at 'localhost' failed
error: 'Access denied for user 'root'@'localhost' (using password: NO)'

Cause

User root with no password is stored in the file /etc/mysql/debian.cnf:

[client]
host = localhost
user = root
password =
socket = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
host = localhost
user = root
password =
socket = /var/run/mysqld/mysqld.sock
basedir = /usr

Solution

• ssh to your server and run the following commands

plesk db

CREATE USER 'root'@'localhost' IDENTIFIED BY 'PASSWORD HERE';

GRANT ALL PRIVILEGES ON *.* TO 'root'@'localhost';

GRANT RELOAD, SHUTDOWN, PROCESS, SHOW DATABASES, SUPER, LOCK TABLES ON *.* TO 'root'@'localhost' IDENTIFIED BY 'PASSWORD HERE';

FLUSH PRIVILEGES;

exit

• Make sure you can login with the account

mysql -u root -p

• Edit config file

nano /etc/mysql/debian.cnf

• Enter the password from above

[client]
host = localhost
user = root
password = "your_password"
socket = /var/run/mysqld/mysqld.sock
[mysql_upgrade]
host = localhost
user = root
password = "your_password"
socket = /var/run/mysqld/mysqld.sock
basedir = /usr

• Test again

mysqladmin --defaults-file=/etc/mysql/debian.cnf --local flush-error-log

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