php mysqli_connect: authentication method unknown to the client [caching_sha2_password]

Php Problem Overview

I am using php mysqli_connect for login to a MySQL database (all on localhost)

<?php
//DEFINE ('DB_USER', 'user2');
//DEFINE ('DB_PASSWORD', 'pass2');
DEFINE ('DB_USER', 'user1');
DEFINE ('DB_PASSWORD', 'pass1');
DEFINE ('DB_HOST', '127.0.0.1');
DEFINE ('DB_NAME', 'dbname');

$dbc = mysqli_connect(DB_HOST, DB_USER, DB_PASSWORD, DB_NAME);

if(!$dbc){
	die('error connecting to database');	
}
?>

this is the mysql.user table:

MySQL Server ini File:

[mysqld]
# The default authentication plugin to be used when connecting to the server
default_authentication_plugin=caching_sha2_password
#default_authentication_plugin=mysql_native_password

with caching_sha2_password in the MySQL Server ini file, it's not possible at all to login with user1 or user2;

> error: mysqli_connect(): The server requested authentication method unknown to the client [caching_sha2_password] in...

with mysql_native_password in the MySQL Server ini file, it's possible to login with user1, but with user2, same error;

how can I login using caching_sha2_password on the mySql Server?

Php Solutions

Solution 1 - Php

I solve this by SQL command:

ALTER USER 'mysqlUsername'@'localhost' IDENTIFIED WITH mysql_native_password BY 'mysqlUsernamePassword';

which is referenced by https://dev.mysql.com/doc/refman/8.0/en/alter-user.html

if you are creating new user

 CREATE USER 'jeffrey'@'localhost' IDENTIFIED WITH mysql_native_password BY 'password';

which is referenced by https://dev.mysql.com/doc/refman/8.0/en/create-user.html

this works for me

Solution 2 - Php

As of PHP 7.4, this is no longer an issue. Support for caching_sha2 authentication method has been added to mysqlnd.

Currently, PHP mysqli extension do not support new caching_sha2 authentication feature. You have to wait until they release an update.

Check related post from MySQL developers: https://mysqlserverteam.com/upgrading-to-mysql-8-0-default-authentication-plugin-considerations/

They didn't mention PDO, maybe you should try to connect with PDO.

Solution 3 - Php

ALTER USER 'mysqlUsername'@'localhost' IDENTIFIED WITH mysql_native_password BY 'mysqlUsernamePassword';

Remove quotes (') after ALTER USER and keep quote (') after mysql_native_password BY

It is working for me also.

Solution 4 - Php

If you're on Windows and it's not possible to use caching_sha2_password at all, you can do the following:

rerun the MySQL Installer
select "Reconfigure" next to MySQL Server (the top item)
click "Next" until you get to "Authentication Method"
change "Use Strong Password Encryption for Authentication (RECOMMENDED)" to "Use Legacy Authentication Method (Retain MySQL 5.X Compatibility)
click "Next"
enter your Root Account Password in Accounts and Roles, and click "Check"
click "Next"
keep clicking "Next" until you get to "Apply Configuration"
click "Execute"

The Installer will make all the configuration changes needed for you.

Solution 5 - Php

Like many many people, I have had the same problem. Although the user is set to use mysql_native_password, and I can connect from the command line, the only way I could get mysqli() to connect is to add

> default-authentication-plugin=mysql_native_password

to the [mysqld] section of, in my setup on ubuntu 19.10, /etc/mysql/mysql.conf.d/mysqld.cnf

Solution 6 - Php

It's working for me (PHP 5.6 + PDO / MySQL Server 8.0 / Windows 7 64bits)

Edit the file C:\ProgramData\MySQL\MySQL Server 8.0\my.ini:

default_authentication_plugin=mysql_native_password

Reset MySQL service on Windows, and in the MySQL Shell...

ALTER USER my_user@'%' IDENTIFIED WITH mysql_native_password BY 'password';

Solution 7 - Php

I ran the following command ALTER USER 'root' @ 'localhost' identified with mysql_native_password BY 'root123'; in the command line and finally restart MySQL in local services.

Solution 8 - Php

If you're on a Mac, here's how to fix it. This is after tons of trial and error. Hope this helps others..

Debugging:

$mysql --verbose --help | grep my.cnf

$ which mysql
/usr/local/bin/mysql

Resolution: nano /usr/local/etc/my.cnf

Add: default-authentication-plugin=mysql_native_password

-------
# Default Homebrew MySQL server config
[mysqld]
# Only allow connections from localhost
bind-address = 127.0.0.1
default-authentication-plugin=mysql_native_password
------

Finally Run: brew services restart mysql

Solution 9 - Php

Now you can upgrade to PHP7.4 and MySQL will go with caching_sha2_password by default, so default MySQL installation will work with mysqli_connect No configuration required.

Solution 10 - Php

I tried this in Ubuntu 18.04 and is the only solution that worked for me:

ALTER USER my_user@'%' IDENTIFIED WITH mysql_native_password BY 'password';

Solution 11 - Php

I am using laravel 5.8 and having MAMP server got this error resolved by adding DB_SOCKET=/Applications/MAMP/tmp/mysql/mysql.sock in .env file like below

DB_CONNECTION=mysql
DB_HOST=127.0.0.1
DB_PORT=8889
DB_DATABASE=dbname
DB_USERNAME=root
DB_PASSWORD=root
DB_SOCKET=/Applications/MAMP/tmp/mysql/mysql.sock

Solution 12 - Php

In my case when I was using WAMP server I fixed it using following

Note the port in mySQL's "my.ini" file. In my case it was changed to 3308 when I was switching b/w MariaDB and MySQL DB.

Use the port number when you create mysqli object.

Using the above steps I was able to run the program successfully.

Solution 13 - Php

phpMyAdmin GUI way

Note: This method may not work if you have the problem with root user account.

Login to phpMyAdmin as root.
Switch to "User Accounts" tab.
Select the username you get error with.
From the top buttons, switch to "Login Information" section.
In "Login Information" box, change "Authentication plugin" from "Caching sha2 authentication" to "Native MySQL authentication". Also, you must fill in other required fields, obviously, including username and password.
Save it by clicking on the "Go" button at the bottom.
Return back to terminal and enjoy. :)

Solution 14 - Php

In my case, i'm using PHP Symfony framework and it's a silly mistake.

The database credential was wrong in paramers.yml.

After changing the credentials accordingly the problem was gone.

Solution 15 - Php

I think it is not useful to configure the mysql server without caching_sha2_password encryption, we have to find a way to publish, send or obtain secure information through the network. As you see in the code below I dont use variable $db_name, and Im using a user in mysql server with standar configuration password. Just create a Standar user password and config all privilages. it works, but how i said without segurity.

<?php
$db_name="db";
$mysql_username="root";
$mysql_password="****";
$server_name="localhost";
$conn=mysqli_connect($server_name,$mysql_username,$mysql_password);

if ($conn) {
	echo "connetion success";
}
else{
	echo mysqli_error($conn);
}

?>

Content Type	Original Author	Original Content on Stackoverflow
Question	Guti_Haz	View Question on Stackoverflow
Solution 1 - Php	黃皓哲	View Answer on Stackoverflow
Solution 2 - Php	abeyaz	View Answer on Stackoverflow
Solution 3 - Php	Eranda J.	View Answer on Stackoverflow
Solution 4 - Php	CJ Dennis	View Answer on Stackoverflow
Solution 5 - Php	dBags	View Answer on Stackoverflow
Solution 6 - Php	Chinnon Santos	View Answer on Stackoverflow
Solution 7 - Php	JRonald Moreno	View Answer on Stackoverflow
Solution 8 - Php	kp123	View Answer on Stackoverflow
Solution 9 - Php	Pavel Niedoba	View Answer on Stackoverflow
Solution 10 - Php	imjesr	View Answer on Stackoverflow
Solution 11 - Php	Zeeshan Mehdi	View Answer on Stackoverflow
Solution 12 - Php	Harsh	View Answer on Stackoverflow
Solution 13 - Php	MAChitgarha	View Answer on Stackoverflow
Solution 14 - Php	sh6210	View Answer on Stackoverflow
Solution 15 - Php	Steven Canales	View Answer on Stackoverflow