and CAUSE: mysqld --no-defaults --verbose --help | egrep ^datadir datadir /var/lib/mysql/ ls -ld /var/lib/mysql lrwxrwxrwx 1 mysql mysql 27 Mar 7 14:13 /var/lib/mysql -> /mnt/rwstore/rwstore/mysql/
and CAUSE: rwstore/ mysql/
mysqld --no-defaults --verbose --help | egrep ^datadir
datadir /var/lib/mysql/
ls -ld /var/lib/mysql
lrwxrwxrwx 1 mysql mysql 27 Mar 7 14:13 /var/lib/mysql -> /mnt/rwstore/