Next cloud and mysql setup: authentication method unknown to the client - mysql

Question

Using the rancher GUI, I'm trying to set up Nextcloud with MySQL database workloads on my AKS cluster. In the environment variables, I already have defined the admin user and password so why do I get this error on the create admin page?
Error while trying to create admin user: Failed to connect to the
database: An exception occurred in driver: SQLSTATE[HY000] [2054] The
server requested authentication method unknown to the client
I entered the Username and password correctly multiple times.
Below are my configurations for the database and nextcloud so far.
database workload:
Name: nextdb
Docker image: mysql
port: not set
I have the following variables:
MYSQL_ROOT_PASSWORD=rootpassX
MYSQL_DATABASE=nextDB
MYSQL_USER=nextcloud
MYSQL_PASSWORD=passX
volumes configuration:
Volume Type: Bind-Mount
Volume Name: nextdb
Path on the Node : /nextdb
The Path on the Node must be: a directory or create
Mount Point: /var/lib/mysql
nextcloud workload:
Name: nextcloud
Docker Image: nextcloud
Port Mapping:
Port Name : nextcloud80
Publish the container port: 80
Protocol: TCP
As a: Layer-4 load balancer
On listening port: 80
Environment variables:
MYSQL_DATABASE=nextDB
MYSQL_USER=nextcloud
MYSQL_PASSWORD=passX
MYSQL_HOST=nextdb
NEXTCLOUD_ADMIN_USER=admin
NEXTCLOUD_ADMIN_PASSWORD=adminPass
NEXTCLOUD_DATA_DIR=/var/www/html/nextcloud
Volumes:
Volume 1:
name: nextcloud
Volume Type: Bind-Mount
Path on the Node: /nextcloud
The Path on the Node must be: a directory or create.
Mount Point: /var/www/html
Volume 2
name: nextdb
Volume Type: Bind-Mount
Path on the Node: /nextdatabase
The Path on the Node must be: a directory or create.
Mount Point: /var/lib/mysql
What are the problems with my configurations?

Answer 1

Starting with version 8.02, MySQL updated the default authentication method for client connections. To revert to the older authentication method you need to explicitly specify the default authentication method.
If you are able to update your DB service in Rancher to pass the container argument --default-authentication-plugin=mysql_native_password that should revert MySQL to the older auth method.
Alternatively, depending on the MySQL image you are using, you can create a new Docker image from that base which replaces /etc/mysql/my.cnf inside the container. You should inspect /etc/mysql/my.cnf before you replace it, if there are any !includedir directives in the config file, you can place your supplemental configuration into an included folder using whatever filename you choose.
The supplemental configuration should look like this:
[mysqld]
default_authentication_plugin=mysql_native_password