1. Note that the default startup user is mysql
2. Due to the root used to execute the command, some files will be generated as the root user
3. Note that the datadir basedir socket dir is changed to mysql chown mysql:mysql dir
4. Note that the mysql database folder and the internal files of the folder generated by datadir are modified to the mysql user
5. If there is no problem with mysql.plugin, execute ./mysql_safe --datadir=xx --basedir=xx --user=mysql & regenerate data
6. If it is python2.x, you need to install mysql-python, download mysql-python and then python setup.py install
7.chown mysql *；chgrp mysql *；chmod ug+rwx *
Solve the problem:
1.Can't find file: '/xxx.frm'
2.Table 'mysql.plugin' doesn't exist