Solved: "authentication method unknown" during installation

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Solved: "authentication method unknown" during installation

Post by hadg »


I ran into the following issue while installing CMSMS 2.3-beta6 on a CentOS 7 server, with Apache 2.4, PHP 7.3 and MySQL (Percona) 8.0.15. I installed from the PHAR file, i.e., cmsms-2.3-beta6-install.php.

After I created a MySQL user and database for CMSMS, I entered these details in the corresponding screen in the installation process, and got the following error:
The server requested authentication method unknown to the client
I found out that MySQL changed the default authentication plugin from mysql_native_password to caching_sha2_password as of version 8.0.4. You can read more about this here: ... 8-0-4.html ... 2-password

This has no effect when MySQL is upgraded in place for an existing CMSMS installation. The problem arises when a new database user is created, in MySQL version 8.0.4 or later.


Code: Select all

mysql> CREATE USER 'cmsuser'@'localhost' IDENTIFIED WITH mysql_native_password BY 'YourPasswordHere';
This creates a database user while expressly selecting mysql_native_password authentication.

I trust that future versions of CMSMS (or perhaps I should say, future versions of the PHP MySQLi extension?) will support the newer SHA2 authentication mechanisms.

I am posting this here in hope that it may be useful to someone. I am new here, so if I posted in the wrong place then please point me in the right direction.


P.S. The eagle-eyed reader may have noticed that I'm on PHP 7.3, while CMSMS 2.3 officially calls for <=7.2. I'm pleased to say I've had no issues so far.
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Re: Solved: "authentication method unknown" during installat

Post by calguy1000 »

quick research says that the mysqli extension to PHP does not support this (yet).
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