Mysql报错 ：Unknown table engine 'InnoDB'

lishenghan

　　问题：
　　zabbix服务器重启后，进入zabbix的web发现登录不进去并且网页报mysql的错误，查看mysql的日之后，发现报错：
　　[root@czy ~]# tail -f /var/log/mysqld.log
　　140820 16:24:43 [Note] /usr/libexec/mysqld: ready for connections.
　　Version: '5.1.73'  socket: '/var/lib/mysql/mysql.sock'  port: 3306  Source distribution
　　140917 15:03:03 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
　　/usr/libexec/mysqld: Can't create/write to file '/tmp/ibEdFc8d' (Errcode: 13)
　　140917 15:03:03  InnoDB: Error: unable to create temporary file; errno: 13
　　140917 15:03:03 [ERROR] Plugin 'InnoDB' init function returned error.
　　140917 15:03:03 [ERROR] Plugin 'InnoDB' registration as a STORAGE ENGINE failed.
　　再查看zabbix的日志之后，也发现报错
　　[root@czy zabbix]#tail -f /tmp/zabbix_server.log
　　3545:20140917:154534.090 [Z3005] query failed: [1286] Unknown table engine 'InnoDB' [select distinct r.druleid,r.iprange,r.name,c.dcheckid from drules r left join dchecks c on c.druleid=r.druleid and uniq=1 where r.proxy_hostid is null and r.status=0 and (r.nextcheck1410939934+r.delay) and mod(r.druleid,1)=0 and r.druleid between 0 and 99999999999999]
　　3545:20140917:154534.090 [Z3005] query failed: [1286] Unknown table engine 'InnoDB' [select count(*),min(nextcheck) from drules where proxy_hostid is null and status=0 and mod(druleid,1)=0 and druleid between 0 and 99999999999999]
　　后百度查询“Unknown table engine 'InnoDB'”的解决办法，一堆文章说需要修改mysql内部设置调整等，心想不会出现mysql内部设置问题，因为就重启了机器发生的问题。后仔细检查mysql报错，看到关键信息“/usr/libexec/mysqld: Can't create/write to file '/tmp/ibEdFc8d' ”  ，此时查看/tmp的权限，果然是错误的权限，因为机器重启后，/tmp的权限会重置。
　　解决办法： chmod 777 /tmp
　　就这样，很简单！  因为Mysql在启动的时候会在/tmp下创建临时文件和 socket 文件，所以/tmp权限不正确了就会报错