T-SQL cannot create SQL Server database file on mounted docker volume - sql-server

Question

I'm trying to create a database in docker and have the .mdf and .ldf files be created on a mounted volume so they're not lost when the container shuts down. I followed Microsoft's instructions and added the volume to their example command like so:
docker run -e 'ACCEPT_EULA=Y' -e 'SA_PASSWORD=<MY_PASSWORD>' \
-p 1433:1433 --name sql1 \
-v ~/mssql/data:/var/data \
-d mcr.microsoft.com/mssql/server:2017-latest
Here's the SQL used to create the database and the files:
CREATE DATABASE [MY_DB]
CONTAINMENT = NONE
ON PRIMARY
( NAME = N'MY_DB', FILENAME = N'/var/data/MY_DB.mdf' , SIZE = 204800KB , MAXSIZE = UNLIMITED, FILEGROWTH = 65536KB )
LOG ON
( NAME = N'MY_DB_log', FILENAME = N'/var/data/MY_DB_log.ldf' , SIZE = 860160KB , MAXSIZE = 2048GB , FILEGROWTH = 65536KB )
I know this currently works if you're on a Windows machine running everything without docker because that's how we currently do it. However, when I try to execute the above SQL from inside the container (by connecting with a RDBMS), I get the error:
CREATE FILE encountered operating system error 2(The system cannot find the file specified.) while attempting to open or create the physical file '/var/data/SVT_MVP.mdf'
I tried execing into the container and running the SQL as root, but I get the same error. For funsies I even tried to chmod the mapped host directory to 0777 but no dice.
Another note is that everything works perfectly fine if there is no volume mounted. At this point I'm questioning if the volume part is worth it or even needed. I'm pretty new to docker.

Answer 1

For those curious, mounting volumes on macos has had issues since 2017. Instead you have to create a data volume (named volume):
docker run -e 'ACCEPT_EULA=Y' -e 'SA_PASSWORD=<MY_PASSWORD>' \
-p 1433:1433 --name sql1 \
-v sqlvolume:/var/opt/mssql/data \
-d mcr.microsoft.com/mssql/server:2017-latest
Thank you to Larnu who pointed me in the right direction.