[root@redflag11012501 mysql]# ls /usr/share/mysql/*cnf/usr/share/mysql/my-huge.cnf /usr/share/mysql/my-large.cnf /usr/share/mysql/my-small.cnf/usr/share/mysql/my-innodb-heavy-4G.cnf /usr/share/mysql/my-medium.cnf[root@redflag11012501 mysql]#cp /usr/share/mysql/my-innodb-heavy-4G.cnf /etc/my.cnf由于Linux的/文件系统空间有限，因此将数据文件目录改到空闲空间较多的/user1/mysql_db。用vi编辑/etc/my.cnf文件。另一种Linux和Unix下可用的方式是在数据库关闭时使用软连接，将数据库目录指向另一个目录。
innodb_data_file_path = ibdata1:1000M:autoextendinnodb_data_home_dir = /user1/mysql_dbinnodb_log_file_size = 256M修改后保存/etc/my.cnf文件，用mysqld命令重新启动服务器，结果报错：
[root@redflag11012501 mysql]# mysqld --user=root110603 10:29:28 [Note] Plugin 'FEDERATED' is disabled.110603 10:29:28 InnoDB: The InnoDB memory heap is disabled110603 10:29:28 InnoDB: Mutexes and rw_locks use GCC atomic builtins110603 10:29:28 InnoDB: Compressed tables use zlib 1.2.3110603 10:29:28 InnoDB: Using Linux native AIO110603 10:29:28 InnoDB: Initializing buffer pool, size = 20.0G110603 10:29:30 InnoDB: Completed initialization of buffer poolInnoDB: The first specified data file /user1/mysql_db/ibdata1 did not exist:InnoDB: a new database to be created!110603 10:29:30 InnoDB: Setting file /user1/mysql_db/ibdata1 size to 1000 MBInnoDB: Database physically writes the file full: wait...InnoDB: Progress in MB: 100 200 300 400 500 600 700 800 900 1000110603 10:29:36 InnoDB: Error: all log files must be created at the same time.110603 10:29:36 InnoDB: All log files must be created also in database creation.110603 10:29:36 InnoDB: If you want bigger or smaller log files, shut down the110603 10:29:36 InnoDB: database and make sure there were no errors in shutdown.110603 10:29:36 InnoDB: Then delete the existing log files. Edit the .cnf file110603 10:29:36 InnoDB: and start the database again.110603 10:29:36 [ERROR] Plugin 'InnoDB' init function returned error.110603 10:29:36 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.110603 10:29:36 [Note] Event Scheduler: Loaded 0 events110603 10:29:36 [Note] mysqld: ready for connections.Version: '5.5.13-log' socket: '/var/lib/mysql/mysql.sock' port: 3306 MySQL Community Server (GPL)110603 10:30:10 [Note] mysqld: Normal shutdown110603 10:30:10 [Note] Event Scheduler: Purging the queue. 0 events110603 10:30:10 [Note] mysqld: Shutdown complete从提示信息可知，原有日志文件和新的数据文件不匹配，需要删除原有的文件。
删除所有数据文件和日志文件，
[root@redflag11012501 mysql]# ll总计 787260-rw-rw---- 1 root root 268435456 06-03 10:26 ib_logfile0-rw-rw---- 1 root root 268435456 06-03 10:26 ib_logfile1-rw-rw---- 1 root root 268435456 06-03 10:26 ib_logfile2drwx--x--x 2 mysql mysql 4096 06-02 17:59 mysql-rw-rw---- 1 root root 126 06-03 10:14 mysql-bin.000001-rw-rw---- 1 root root 126 06-03 10:24 mysql-bin.000002-rw-rw---- 1 root root 126 06-03 10:26 mysql-bin.000003-rw-rw---- 1 root root 126 06-03 10:30 mysql-bin.000004-rw-rw---- 1 root root 76 06-03 10:29 mysql-bin.indexdrwx------ 2 mysql mysql 4096 06-02 17:59 performance_schema-rw-rw---- 1 mysql root 2079 06-03 09:44 redflag11012501.err-rw-rw---- 1 root root 692 06-03 10:29 redflag11012501-slow.log-rw-r--r-- 1 root root 121 06-02 17:59 RPM_UPGRADE_HISTORY-rw-r--r-- 1 mysql mysql 121 06-02 17:59 RPM_UPGRADE_MARKER-LASTdrwxr-xr-x 2 mysql mysql 4096 06-02 17:59 test[root@redflag11012501 mysql]# rm ib_logfile*rm：是否删除 一般文件 “ib_logfile0”? trm：是否删除 一般文件 “ib_logfile1”? trm：是否删除 一般文件 “ib_logfile2”? t[root@redflag11012501 mysql]# rm mysql-bin*rm：是否删除 一般文件 “mysql-bin.000001”? trm：是否删除 一般文件 “mysql-bin.000002”? trm：是否删除 一般文件 “mysql-bin.000003”? trm：是否删除 一般文件 “mysql-bin.000004”? trm：是否删除 一般文件 “mysql-bin.index”? t[root@redflag11012501 mysql]# rm /user1/mysql_db/*rm：是否删除 一般文件 “/user1/mysql_db/ibdata1”? y同时将日志文件目录也修改，重新启动就可以了。
