Recently I met a lot of pit at the time of installation mysql5.6. In particular yum install mysql-server, the download is always mysql8, causing many problems. Finally, because I found is that centos8, centos8 support mysql version is 8.0. So the Internet looked, it was summed up a lot, such as: Centos8 difference and 7 (see redhat) https://www.cnblogs.com/iwalkman/p/11781234.html
Finally, the server console or in exchange for Ali familiar centos7.
My main concern is the following, and the other on the line know the difference between:
