root@ubuntu:/usr/local/mysql# ./bin/mysql.server restart
Shutting down MySQL
.. *
Starting MySQL
...... * The server quit without updating PID file (/usr/local/mysql-5.7.21-linux-glibc2.12-x86_64/data/ubuntu.pid).
[mysqld]
prompt=(\u@\h) [\d]>\ 去掉这个一行..... 自己加的引起问题