Cannot upgrade server earlier than 5.7 to 8.0 in centos. server start fail

Question

I try to configure Mysql server on centos 7.4. After installing Mysql 8.0 to my system, systemctl restart mysqld failed.

See the error log /var/log/mysqld.log.

[System] [MY-010116] [Server] /usr/sbin/mysqld (mysqld 8.0.11) starting as process 320 [ERROR] [MY-013168] [InnoDB] Cannot upgrade server earlier than 5.7 to 8.0 [ERROR] [MY-011013] [Server] Failed to initialize DD Storage Engine.[ERROR] [MY-010020] [Server] Data Dictionary initialization failed. [ERROR] [MY-010119] [Server] Aborting [System] [MY-010910] [Server] /usr/sbin/mysqld: Shutdown complete (mysqld 8.0.11) MySQL Community Server - GPL.

Answer 1

You have to delete the files left from the previous MySql:

rm -rf /var/lib/mysql/*