I tried replicating from Amazon Aurora MySQL v3 to v2 in the reverse direction, and it works, at least for now.
This is Onikai (@fat47) from the Service Reliability Group (SRG) of the Technology Division.
#SRGThe Service Reliability Group primarily provides comprehensive support for the infrastructure surrounding our media services, focusing on improving existing services, launching new ones, and contributing to open-source software (OSS).
This article is located within SRG.DBWGThe DB Working Group is releasing database-related materials that it provides to the entire company.
I hope this is of some help.
!! Note !!Replicant in the opposite direction?In a standard MySQL database, attempting to replicate in the reverse direction will normally result in an error.Why is it okay with Aurora MySQL?In conclusion
!! Note !!
The configuration described in this article is deprecated by both MySQL and AWS.
Please note that this is merely a report that it worked.
Replicant in the opposite direction?
We are currently using Aurora Version 3 as the source and Version 2 as the replica, with replication between clusters.
In case you need to roll back to v2 during an upgrade from v2, I've included a link to a deprecated version replication for that purpose.
In a standard MySQL database, attempting to replicate in the reverse direction will normally result in an error.
I've written about this before on this blog.
When setting up replication with MySQL 8.0 as the source and MySQL 5.7 as the replica, the replication immediately stops with an error.
@@session.collation_connection=255To avoid this, you need to specify the following in the MySQL 8.0 configuration to fix the default behavior of collation to utf8_general_ci.
By the way, the default_collation_for_utf8mb4 setting cannot be applied in Aurora.
Why is it okay with Aurora MySQL?
This is also an excerpt from a past article.
Aurora Version 2 (MySQL 5.7 compatible) includes a unique implementation of `utf8mb4_0900_ai_ci` for `collation`, which is not included in the original MySQL 5.7.
Therefore, even if you configure replication with Aurora v3 as the source and Aurora v2 as the replica,
Collation errors do not cause replication to stop.
In conclusion
Please note that these methods are strictly discouraged.
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