Charles Bao :
I've set up a slave replication of MySQL database. And for development requirements, I want to write sth into the slave database, but it would cause the broken of replication.
Since the database is huge, I don't want to restore the slave database from MySQL dump file every time after I finished some development work.
My requirement:
All the changes in the slave database can be reverted by a simple command.
The replication keeps working.
Bill Karwin :
One method is to use LVM filesystem snapshots. Before you begin testing:
- Stop replication.
- Take an LVM snapshot.
- Do your tests. Replication is still off, but data is up to date
After you finish testing:
- Stop mysqld.
- Restore the snapshot. This reverts all files to the state they were at the moment you created the LVM snapshot above.
- Start mysqld and start replication. It will need to catch up and apply all changes since you stopped replication before your testing. This will take a little while, depending on how many changes happened on your master database.
See https://www.tecmint.com/take-snapshot-of-logical-volume-and-restore-in-lvm/ for a nice tutorial on using LVM snapshots.
This method only works if your development database instance is on Linux.