I am new to MySQL and Linux and because I had issues with an old MySQL version (5.1) I used mysqldump and installed MySQL 5.6. I changed the datadir location by copying everything to the new folder and set a symbolic link in the default directory to my new folder. I set the permissions to 755 and the user und group is mysql. With ls -aZ I get:drwxr-xr-x. mysql    mysql    unconfined_u:object_r:mysqld_db_t:s0 mysqlThe exact error messages are:with mysql_install_db --user=mysql --datadir=new_dir:[Note] InnoDB: 5.6.24 started; log sequence number 1600717ERROR: 1036  Table 'db' is read only[ERROR] Abortingin /var/log/mysqld.log I found:[ERROR] Can't open the mysql.plugin table. Please run mysql_upgrade to create it.[ERROR] Fatal error: Can't open and lock privilege tables: Table 'user' is read only`But I can't run mysql_upgrade because mysql is not running. I always get:    MySQL Daemon failed to start.    Starting mysqld:  [FAILED]when trying: service mysqld startIf you have any suggestions how to solve this, please let me know. They are very appreciated!UPDATE:Thanks to apaul for the suggestions!I installed the repository for yum and then further installed mysql by yum.I only copied the mysql folder and the ibdata1, ib_logfile0, ib_logfile1 files and performance-scheme which appeared after mysql installation. Because I didn't dumped and didn't deleted the mysql folder in contrast to my real data databases. As suggested here.I already use the --datadir as well as --user=mysql when performing mysql_install_db command.All directories for mysql are 755 so should be executable. But I think - as I remember correct -  it was only 700 before the change to 5.6.What I also tested: restarting the PC and I tried in the my.cnf the real path to the datadir and the path to the symlink.
MySQL read only error but permissions set and SELinux AFAICT correct
centos;permissions;mysql