[debian-mysql] Bug#845648: mention how to deal with Pre-4.1 password hash found. It is deprecated and will be removed in a future release. Please upgrade it to a new format warning

[積丹尼 Dan Jacobson]

Package: mysql-server
Version: 5.7.16-1

Upon upgrade user sees

 Pre-4.1 password hash found. It is deprecated and will be removed in a future release. Please upgrade it to a new format.

This message is not enough.

There is only one user on the system.

How does user reset this (which?) password?

Yes I am willing to type my password in again. What is it? A user
password? A system password? A database password? What? Which user?

How does user check that the problem is then fixed?

A search on the internet does not find any exact answers!

Nor does /usr/share/doc/mysql-server/ .