DM运维踩坑实践总结

{"type":"doc","content":[{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"背景"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"在早期从MySQL到TiDB实施同步操作过程中，我们大多数用的是mydumper+loader进行整体全量备份的导出，之后拿到meta信息后，通过syncer实现增量同步，整体操作起来比较麻烦，涉及的配置文件较多，其基本原理就是Syncer 通过把自己注册为一个 MySQL Slave 的方式，和 MySQL Master 进行通信，然后不断读取 MySQL Binlog，进行 Binlog Event 解析，规则过滤和数据同步。其架构如下："}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"image","attrs":{"src":"https:\/\/static001.infoq.cn\/resource\/image\/c0\/3b\/c01b24ac6a5a35f635f779640bbe413b.png","alt":null,"title":"","style":[{"key":"width","value":"75%"},{"key":"bordertype","value":"none"}],"href":"","fromPaste":false,"pastePass":false}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null},"content":[{"type":"text","text":"而后pingcap官方推出了TiDB Data Migration (DM)套件，这一套件极大地降低了同步工具使用的门槛。DM是一体化的数据迁移任务管理平台，支持从 MySQL 或 MariaDB 到 TiDB 的全量数据迁移和增量数据复制。使用 DM 工具有利于简化错误处理流程，降低运维成本。后续更是有dm-portal工具方便dba通过图形化界面的方式进行选择性导出和自动生成配置文件，虽然有一些小bug和不够人性化的方面，但无伤大雅，可惜的是这个项目最后咨询官方得知被砍掉了，不再进行维护。"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}},{"type":"heading","attrs":{"align":null,"level":2},"content":[{"type":"text","text":"原因"}]},{"type":"paragraph","attrs":{"indent":0,"number":0,"align":null,"origin":null}}]}