症状：无法启动mysql，在“mysql数据库目录/主机名.err”日志文件中报错 Unknown/unsupported storage engine: InnoDB
原因：MySQL5.5.8 GA默认引擎为InnoDB，而配置文件（my.cnf）中设置了skip-innodb
解决：在配置文件（my.cnf）中设置default-storage-engine=MyISAM

Error：
2013-08-18 21:08:37 21440 [Note] Plugin ‘FEDERATED‘ is disabled.
2013-08-18 21:08:37 21440 [Note] Plugin ‘InnoDB‘ is disabled.
2013-08-18 21:08:37 21440 [ERROR] Unknown/unsupported storage engine: InnoDB

My.cnf修改成这样就Ok了：
#loose-skip-innodb            
default-storage-engine = MyISAM

加上#号后启动Ok：
mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.6.13 Source distribution

Unknown/unsupported storage engine: InnoDB