[php] PHP with MySQL 8.0+ error: The server requested authentication method unknown to the client

I'm running MySQL version 8 on PHP 7.0.

I'm getting the following error when I try to connect to my database from PHP:

Connect Error: SQLSTATE[HY000] [2054] The server requested authentication method unknown to the client

PHP might show this error

Warning: mysqli_connect(): The server requested authentication method unknown to the client [caching_sha2_password] in D:\xampp\htdocs\reg\server.php on line 10

How can I fix this problem?

This question is related to php mysql mysql-8.0

The answer is


Faced the same problem, I was not able to run wordpress docker container with mysql version 8 as its default authentication mechanism is caching_sha2_password instead of mysql_native_password.

In order to fix this problem we must reset default authentication mechanism to mysql_native_password.

Find my.cnf file in your mysql installation, usually on a linux machine it is at the following location - /etc/mysql

Edit my.cnf file and add following line just under heading [mysqld]

default_authentication_plugin= mysql_native_password

Save the file then log into mysql command line using root user

run command FLUSH PRIVILEGES;


In my.cnf file check below 2 steps.

  • check this value -

    old_passwords=0;

    it should be 0.

  • check this also-

    [mysqld] default_authentication_plugin= mysql_native_password Another value to check is to make sure

    [mysqld] section should be like this.


preferences -> mysql -> initialize database -> use legacy password encryption(instead of strong) -> entered same password

as my config.inc.php file, restarted the apache server and it worked. I was still suspicious about it so I stopped the apache and mysql server and started them again and now it's working.


i've try a lot of ways, but only this work for me

thanks for workaround

check your .env

MYSQL_VERSION=latest

then type this command

$ docker-compose exec mysql bash
$ mysql -u root -p 

(login as root)

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'root';
ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY 'root';
ALTER USER 'default'@'%' IDENTIFIED WITH mysql_native_password BY 'secret';

then go to phpmyadmin and login as :

  • host -> mysql
  • user -> root
  • password -> root

hope it help


@mohammed, this is usually attributed to the authentication plugin that your mysql database is using.

By default and for some reason, mysql 8 default plugin is auth_socket. Applications will most times expect to log in to your database using a password.

If you have not yet already changed your mysql default authentication plugin, you can do so by:
1. Log in as root to mysql
2. Run this sql command:

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password
BY 'password';  

Replace 'password' with your root password. In case your application does not log in to your database with the root user, replace the 'root' user in the above command with the user that your application uses.

Digital ocean expounds some more on this here Installing Mysql


I'm using Laravel Lumen to build a small application.
For me it was because I didn't had the DB_USERNAME defined in my .env file.

DB_USERNAME=root

Setting this solved my problem.


None of the answers here worked for me. What I had to do is:

  1. Re-run the installer.
  2. Select the quick action 're-configure' next to product 'MySQL Server'
  3. Go through the options till you reach Authentication Method and select 'Use Legacy Authentication Method'

After that it works fine.


You have to change MySQL settings. Edit my.cnf file and put this setting in mysqld section:

[mysqld]
default_authentication_plugin= mysql_native_password

Then run following command:

FLUSH PRIVILEGES;

Above command will bring into effect the changes of default authentication mechanism.


Examples related to php

I am receiving warning in Facebook Application using PHP SDK Pass PDO prepared statement to variables Parse error: syntax error, unexpected [ Preg_match backtrack error Removing "http://" from a string How do I hide the PHP explode delimiter from submitted form results? Problems with installation of Google App Engine SDK for php in OS X Laravel 4 with Sentry 2 add user to a group on Registration php & mysql query not echoing in html with tags? How do I show a message in the foreach loop?

Examples related to mysql

Implement specialization in ER diagram How to post query parameters with Axios? PHP with MySQL 8.0+ error: The server requested authentication method unknown to the client Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver' phpMyAdmin - Error > Incorrect format parameter? Authentication plugin 'caching_sha2_password' is not supported How to resolve Unable to load authentication plugin 'caching_sha2_password' issue Connection Java-MySql : Public Key Retrieval is not allowed How to grant all privileges to root user in MySQL 8.0 MySQL 8.0 - Client does not support authentication protocol requested by server; consider upgrading MySQL client

Examples related to mysql-8.0

PHP with MySQL 8.0+ error: The server requested authentication method unknown to the client How to grant all privileges to root user in MySQL 8.0 phpMyAdmin on MySQL 8.0 Authentication plugin 'caching_sha2_password' cannot be loaded How do you use the "WITH" clause in MySQL?