[root@localhost mysql]# ls -l
total 176164
drwx------ 2 root root 4096 Nov 6 11:07 aazj
-rw-rw---- 1 mysql mysql 543 Nov 6 11:13 general.log
-rw-r----- 1 root root 79691776 Nov 6 11:07 ibdata1
-rw-r----- 1 root root 50331648 Nov 6 11:07 ib_logfile0
-rw-r----- 1 root root 50331648 Nov 6 11:07 ib_logfile1
-rw-rw---- 1 mysql mysql 543 Nov 6 11:13 localhost-slow.log
drwx------ 2 root root 4096 Nov 6 11:07 mysql
-rw-rw---- 1 mysql mysql 0 Nov 6 11:12 mysql-bin.index
drwx------ 2 root root 4096 Nov 6 11:07 performance_schema
drwx------ 2 root root 4096 Nov 6 11:07 t
-rw-r----- 1 root root 24 Nov 6 11:07 xtrabackup_binlog_pos_innodb
-rw-r----- 1 root root 487 Nov 6 11:07 xtrabackup_info
[root@localhost mysql]# chown -R mysql:mysql /var/lib/mysql
[root@localhost mysql]# ls -l
total 176164
drwx------ 2 mysql mysql 4096 Nov 6 11:07 aazj
-rw-rw---- 1 mysql mysql 543 Nov 6 11:13 general.log
-rw-r----- 1 mysql mysql 79691776 Nov 6 11:07 ibdata1
-rw-r----- 1 mysql mysql 50331648 Nov 6 11:07 ib_logfile0
-rw-r----- 1 mysql mysql 50331648 Nov 6 11:07 ib_logfile1
-rw-rw---- 1 mysql mysql 543 Nov 6 11:13 localhost-slow.log
drwx------ 2 mysql mysql 4096 Nov 6 11:07 mysql
-rw-rw---- 1 mysql mysql 0 Nov 6 11:12 mysql-bin.index
drwx------ 2 mysql mysql 4096 Nov 6 11:07 performance_schema
drwx------ 2 mysql mysql 4096 Nov 6 11:07 t
-rw-r----- 1 mysql mysql 24 Nov 6 11:07 xtrabackup_binlog_pos_innodb
-rw-r----- 1 mysql mysql 487 Nov 6 11:07 xtrabackup_info
不然启动会在error.log中报错：
2015-11-06 11:13:55 3542 [ERROR] InnoDB: ./ibdata1 can't be opened in read-write mode
2015-11-06 11:13:55 3542 [ERROR] InnoDB: The system tablespace must be writable!
2015-11-06 11:13:55 3542 [ERROR] Plugin 'InnoDB' init function returned error.
2015-11-06 11:13:55 3542 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
2015-11-06 11:13:55 3542 [ERROR] Unknown/unsupported storage engine: InnoDB
2015-11-06 11:13:55 3542 [ERROR] Aborting
启动成功之后，datadir目录下各种文件都产生了：
[root@localhost mysql]# pwd
/var/lib/mysql
[root@localhost mysql]# ls
aazj general.log ib_logfile0 localhost-slow.log mysql-bin.000001 performance_schema xtrabackup_binlog_pos_innodb