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使用rsync配置了大量mysql，省去了大量编译和配置的时间，随逐个修改master和slave服务器的my.cnf，后，发现数据不能同步，
在slave服务器show slave status:
Fatal error: The slave I/O thread stops because master and slave have equal MySQL server UUIDs; these UUIDs must be different for replication to work.
首先检查：
mysql> show variables like ‘server_id';
+―――――+――-+
| Variable_name | Value |
+―――――+――-+
| server_id | 3 |
+―――――+――-+
主从并不一样，排除该问题。
继续排查，找到原因在于，拷贝整个data目录，把auto.cnf文件也拷贝过来了，里面记录了数据库的uuid，每个库的uuid应该是不一样的。
[auto]
server-uuid=6dcee5be-8cdb-11e2-9408-90e2ba2e2ea6
解决办法，按照这个16进制格式，随便改下，重启mysql即可。
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