Move home data directory failed

[Edward Sun]

Hello, please help ASAP. I tried to move the home data directory to a separate LUN (directory). But afterward, mysqld faied to start. I'm running MySQL 5.7 in Cento 6.8. What's wrong my process?

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# service mysqld stop
# mv /var/lib/mysql /mysqlsys
# ln -s /mysqlsys/mysql /var/lib/mysql

# ls -ld /mysqlsys/mysql
drwxr-x--x. 7 mysql mysql 4096 Mar 20 19:20 /mysqlsys/mysql
# ls -ld /var/lib/mysql
lrwxrwxrwx. 1 root root 15 Mar 20 19:24 /var/lib/mysql -> /mysqlsys/mysql

# service mysqld start
/usr/bin/mysqld_safe: line 586: /var/lib/mysql/mysqld_safe.pid: Permission denied
awk: (FILENAME=- FNR=1) warning: error writing standard output (Broken pipe)
2017-03-21T06:36:31.217493Z mysqld_safe Directory '/var/lib/mysql' for UNIX socket file don't exists.
MySQL Daemon failed to start.
Starting mysqld: [FAILED]