Postfix, mysql, dovecot db connection issue

I'm following the instructions here:

Was able to use mysql v 8.0 after I had to update the repository for mysql.

All went well until I tested with:
sudo postmap -q mysql:/etc/postfix/

I then received a message referencing the mariadb:
postmap: warning: connect to mysql server Authentication plugin 'caching_sha2_password' cannot be loaded: /usr/lib/x86_64-linux-gnu/mariadb18/plugin/ cannot open shared object file: No such file or directory
postmap: fatal: table mysql:/etc/postfix/ query error: No such file or directory

Not sure what to do next??!

2 Replies

The error you're getting is indicating that the authentication plugin isn't installed. You can get around this by changing your password encryption using the SQL command ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'YourPassword';, where YourPassword is the password you want to use for MySQL. This will change the encryption format so that it doesn't require the caching_sha2_password plugin. This should also resolve the "query error", since it looks like you're getting the query error as a result of not being able to authenticate to MySQL.

With all due respects to @jyoo, I would figure out why mysql can't find the caching_sha2_password plugin. mysql_native_passwords are not very secure:

SHA-1 was deprecated in 2011:

-- sw

Update It seems that MariaDB server doesn't yet implement the caching_sha2_password plugin:

That's really awful…it must be proprietary to Oracle! You should check this out:


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