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【DM版本】:V8
【操作系统】：win10
【CPU】:i5
【问题描述】*：通过DM数据迁移工具将mysql库迁移至达梦数据库时，连接mysql数据库失败。错误信息如下：
The last packet successfully received from the server was 7 milliseconds ago. The last packet sent successfully to the server was 4 milliseconds ago.