As a bleeding-edge early adopter, here in June 2018 I am already using Ubuntu 18.04 LTS for new sites I’m setting up for clients. (How daring!)
I ran aground this afternoon with a new server setup, because I couldn’t log into phpMyAdmin as
root (or, therefore, as anyone, since I hadn’t set up my own user yet).
All of the old familiar ways I had been trying, and the tutorials I had referred to for at least the past two years, were not working. So then I specifically searched for a solution for Ubuntu 18.04 and found this excellent tutorial.
mysql_secure_installation wasn’t working. That was one of the “old familiar ways” I had already tried thrice. THRICE I TELL YOU!
The key, I think, was these two unexpected lines:
$ sudo mkdir -p /var/run/mysqld
$ sudo chown mysql:mysql /var/run/mysqld
Because that folder didn’t exist and/or didn’t have the proper permissions, some other steps were failing silently or giving error messages that failed to point me in the direction of the actual problem.
The other thing to note is that with the version of MySQL included in Ubuntu 18.04, these are the proper MySQL commands to run:
UPDATE user SET authentication_string=PASSWORD("linuxconfig.org") WHERE User='root';
UPDATE user SET plugin="mysql_native_password" WHERE User='root';
And it is actually important to run both of those
UPDATE commands, because in the tutorial the results displayed show that the first one updated a record for them, while the second didn’t. I had already run the first command (but not the second) in one of my failed updates. So when I ran these, the first one didn’t update any records and the second one did.