MySQL 5.6.21, 5.7.5以降では、server_idかぶりやserver_uuidかぶりでマシなエラーを吐くようになったらしい

準同期レプリケーションでStop/Startのログが大量に出力される・・・。 : しがないエンジニアのつぶやき を拝見して、そういえばこんなBugがクローズされてなかったっけ？ と思い出したので試してみた。

MySQL Bugs: #72578: Duplicate slave server_uuid in replication forum gives no specific error message

シンプルにカブらせてSTART SLAVEしてみる。


Master - Slaveでserver_uuidカブり。

2014-10-22T02:15:32.090514Z 4 [Note] Slave I/O thread: connected to master 'root@127.0.0.1:64056',replication started in log 'FIRST' at position 4
2014-10-22T02:15:32.275705Z 4 [ERROR] Slave I/O: 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. Error_code: 1593

Master - Slaveでserver_idカブり。

2014-10-22T10:10:23.047895Z 2 [Note] Slave I/O thread: connected to master 'root@127.0.0.1:64056',replication started in log 'bin.000006' at position 147
2014-10-22T10:10:23.049217Z 2 [ERROR] Slave I/O: Fatal error: The slave I/O thread stops because master and slave have equal MySQL server ids; these ids must be different for replication to work (or the --replicate-same-server-id option must be used on slave but this does not always make sense; please check the manual before using it). Error_code: 1593
2014-10-22T10:10:23.049264Z 2 [Note] Slave I/O thread exiting, read up to log 'bin.000006', position 147

Slave同士のserver_uuidカブり。

2014-10-22T10:16:52.643392Z 2 [Note] Slave: received end packet from server due to dump thread being killed on master. Dump threads are killed for example during master shutdown, explicitly by a user, or when the master receives a binlog send request from a duplicate server UUID <940d4a6d-59d3-11e4-91ef-001a4aa000e2> : Error
2014-10-22T10:16:52.643440Z 2 [Note] Slave I/O thread: Failed reading log event, reconnecting to retry, log 'bin.000006' at position 147

わかりやすくなってるー :)

ところで、Slave同士のserver_idカブりはエラーにならず再接続も発生せずフツーに2台に更新が伝播されたんだけど、server_uuid使ってるとこうなるようになったんだっけ…？ （わからん）