First upgrade CENTOS7, then install MARIADB, and then die you almost three o'clock or can't sleep.

Upgrade to CentOS 7, want to install a MySQL, be told:

"Sorry, I didn't notice you are CentOS7, as another Netizen said, after MySQL was acquired by Oracle, the CentOS community was concerned about the copyright or its features of the successor version. Conversion of the default database management system. “

This logic, not very understand, and then Mariadb Bai.

Then service mysqld start is out of date. (but can still be used), redirected to Systemctl this thing.

What is this thing? I don't know, but I feel like a misleading person.

Systemctl Start mariadb

According to Murphy's law, things can never go down as they are supposed to, and it's inevitable to report a mistake. So you see this crap:

Then you see this as prompted:

This is to get you into a trap. None of this is going to work, and it's no use doing a level two. also drunk.

So, where to look?

My own experience is that

Locate the log folder:

Order, because I don't know which one to look at.

Just this boot.

It really is the start of the message. But there's a different hint.

Systemctl Status Mariadb.service

The log file you're dreaming of is here.

With a normal hint of error, things are much better.

The answer is to delete a similar document. It is recommended that the backup be deleted, although I finally deleted it directly.

Cd/var/lib/mysql

MV ib_logfile* ~

Also reported error, port occupancy: This simple, kill process

Still wrong: Can't find mysql.host:mysql_install_db

Also wrong: Can ' t find file: './mysql/host.frm ': Actually not found, is not the right:

Cd/var/lib/mysql

CD MySQL

Chown MySQL *
CHGRP MySQL *
chmod ug+rwx *

Also wrong: Incorrect information in file: './mysql/proxies_priv.frm ', incorrect information? deleted directly. (not recommended, backup recommended)

Rm-f proxies_priv*

Systemctl Start mariadb

It's 49 o ' 2 o'clock in the morning.

First upgrade CENTOS7, then install MARIADB, and then die you almost three o'clock or can't sleep.