در mysql 8.1 چنانچه خطای ذیل هنگام ورود به phpmyadmin نمایش داده شد اقدام زیر را انجام دهید:

خطا:

mysqli_real_connect(): The server requested authentication method unknown to the client [caching_sha2_password]

اقدام:

در کنسول mysql دستور زیر را واردکنید:

1- Log in to MySQL console with root user:

mysql -u root -p PASSWORD

And type the root's password to auth.

2- I created a new user:

mysql> CREATE USER 'user'@'%' IDENTIFIED BY 'password';

3- Grant all privileges to the new user:

mysql> GRANT ALL PRIVILEGES ON *.* To 'user'@'%';

4- Change the Authentication Plugin with the password:

mysql> ALTER USER user IDENTIFIED WITH mysql_native_password BY 'PASSWORD';

Now, phpmyadmin works fine logging the new user.