Mysql not starting in a docker container on MacOS after docker update

Question

I just upgraded to Docker Desktop 2.4 on MacOS, from version 2.3. Suddenly none of my mysql containers will start. The logs show this as the reason:

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Answer 1

The lower_case_table_names setting tells mysql how to store and compare table names. If the file system the database is stored on is itself not case-sensitive, it will force you to use lower_case_table_names=2.

The MacOS filesystem is not case-sensitive. Up until Docker Desktop 2.4, the mysql container apparently didn't know that the underlying filesystem is not case-sensitive and set lower_case_table_names=0. However, since upgrading to Docker 2.4, Docker is apparently smarter about how it mounts volumes. So the container realizes its running on a case-insensitive filesystem and forces lower_case_table_names=2. The problem is that you cannot change the value of lower_case_table_names after initializing the database. And since the data dictionary was initialized with lower_case_table_names=0, it will fail to initialize with the server set to lower_case_table_names=2.

The only solution I've found is to:

1. Downgrade to Docker Desktop 2.3
2. Backup the entire database
3. Upgrade to Docker 2.4
4. Delete the volume storing the database.
5. Reinitialize the database.
6. Restore the database from backup.

UPDATE: See this answer below for a better solution. There is apparently no need to downgrade. You can instead disable "gRPC Fuse for filesharing", backup the database, re-enable gRPC fuse, delete your database data folder, and restore the database from backup.