History (the question is in 2020 below)
2018. After the fresh install of 18.04, two years ago, I wanted to use my
/etc/mysql/my.cnf setup from 16.04 to get things back to what they were. But the MySQL install sets two symlinks
/etc/mysql/my.cnf -> /etc/alternatives/my.cnf
/etc/alternatives/my.cnf -> /etc/mysql/mysql.cnf
thus I replaced the new
/etc/mysql/mysql.cnf with my old 16.04
Things went fine until another MySQL update, which, for some reasons, had my
mysql.cnf replaced with the new one. Bug? Did I accept the replacement? Don't think so, but, well, that's always possible.
So what I did at the time was to bypass the alternatives system, i.e. replace the
/etc/mysql/my.cnf link with my
my.cnf file, and zeroed
my.cnf takes precedence over
mysql.cnf that worked (I think I tried to symlink
mysql.cnf to my
my.cnf file, and there were other trouble, don't remember).
(To be honest, didn't like much the alternatives implementation that I found, cumbersome and counter-intuitive)
2020. Did an upgrade from 18.04 to 20.04. And naturally, MySQL re-created a clean environment with the alternatives links. Good.
However, to complete the upgrade, this time I'd like to keep things clean, and as much as possible
- keep using the alternatives system or not (depending on your advice)
- ensure that a further MySQL upgrade (unless it's v. 9) won't overwrite my setup (or it asks)
What is the recommended way to keep a clean MySQL install?