- Plesk for Linux
The backup task is running on the server in Tools & Settings > Backup Manager.
All websites are not accessible with the following errors:
Error establishing a database connection
504 gateway timeout
Database assigned to affected websites is not accessible with the error:
ERROR 1203 (42000): User database_admin_user already has more than 'max_user_connections' active connections
or the following if checking via Domains > example.com > Databases > database_name > phpMyAdmin:
mysqli::real_connect(): (HY000/1203): User database_admin_user already has more than 'max_user_connections' active connections
Mysqldump locks all tables, and after that performs a data backup, which leads to the growth of number of connections waiting in a queue, and to the error when the defined
max_user_connections value is reached.