Rollback Mysql version after upgrade

MySQL & MariaDB
1

Hi There
Hope all is well.
We have run into an issue after a mysql upgrade to 8.0.36-28 from 8.0.28-19. We seem to be having endless locks on the db’s.
Would like to know the process for rolling back to the previous version. What are the options.

Thanks

2

Hi @Bones52,

I think it is well established that downgrade to a previous version is not supported in MySQL 8. It has been documented and also blogged.

Downgrade from a MySQL 8.0 release to a previous MySQL 8.0 release, is not supported. The only supported alternative is to restore a backup taken before upgrading.

So, the option you have would be to restore from your last backup OR try-dump-load the data from current to older version may be on a different server (probably excluding system tables). Suggest you to test but yes, no rollback; sorry.

Thanks,
K

3

Thank you so much for that prompt response. Will try that suggestion. :+1:

4

Physical backups are not supported for upgrade so depending on the data set size you might find mydumper useful (multi threaded).

1 Like
5

Good luck getting a working backup… 8.0.28-19 was known quite a bit to have backup issues I had a issue with one of the 5 in my cluster and could NOT get a backup restored. I was told someplace on this site that all the .26-30 versions in MySQL had issues and was strongly suggested to upgrade… After spending 2-3 days TRYING to get a backup restored I upgraded all the other nodes and had no issues… (This was in the Cluster version though)