"i18n.site--- via discuss" discuss@lists.mariadb.org writes:
At this point, I manually create a brand new, empty slave database u2 (with no data) to synchronize with this new master. The Slave_IO_Running and Slave_SQL_Running status on u2 are both Yes. I attempt to create a new database on the master, and it appears on u2 as well.
However, the problem is that the old databases present on u3 are not showing up on u2. ( see this image https://p.3ti.site/1712458958.webp )
I have searched online for solutions and it seems like I would need to manually back up the old databases, import them
Yes. MariaDB replication is a facility for asynchroneous replication of changes between servers, but it is not a cluster manager. Such managers are often built on top of replication. You can check if "orchestrator" has a facility to automatically provision a new slave for you.
There is and old MDEV-7502 for automatic slave provisioning from within the server, but it is not currently being worked on, IIUC:
https://jira.mariadb.org/browse/MDEV-7502
, and then modify the binlog files and synchronization positions.
This however is not necessary since you are using GTID. The GTID position can be used directly to start replication, without any manual modifications.
For example back up the master like this:
mysqldump --master-data --single-transaction --gtid ...
Restoring this dump on the new slave will automatically set the GTID position ready for starting replication.
- Kristian.