Help with docker not in Community Apps and Volume Mapping

[scottw]

Hello. I am a bit over my head here and could use some help.

I created a SQL Server 2019 docker by following these instructions:
https://learn.microsoft.com/en-us/sql/linux/quickstart-install-connect-docker?view=sql-server-ver15&pivots=cs1-bash

 

Everything has been working great for a couple of years now. I am now learning more and realized I increased my docker image to a size too big (and wasteful) due to my lack of knowledge. I would now like to size that docker image down and know how to do it the preferred way. Since this docker container was not created through Community Apps, I would have to do it from scratch....not a problem. I would however like to save the DB inside of that container. I can connect to that DB with SQL Server Management Studio but have no idea how to backup the DB OUTSIDE of the docker container...LOL

I realize this should be simple but I am just not up to speed with all of that yet...but am learning. I understand how the Volume Mapping works but it appears my docker container does not have any mapped. Is this something I could do manually to accomplish what I want to accomplish or is there and easier way. Like I said, I just need to be able to backup my Sql DB somewhere safe so I can restore it after I recreate the Docker.img file.

Here is the container, if that helps:

 

 

Thanks,

Scott

Edited August 12, 2023 by scottw

[JonathanM]

Theoretically you should be able to add a path mapping with the container side pointed to a convenient folder like /backup and the host side pointed to /mnt/user/appdata/sql or something like that, then execute the backup inside the container pointed at /backup and the files should show up in /mnt/user/appdata/sql.

[scottw]

Yeah, exactly what I was thinking but have no idea how to do that. I know how to do it by editing a “Community Apps” docker but not this one, it just just allows me to get to the console. 
any idea how to do that or somewhere I can read up on that?

Thanks,

Scott

[scottw]

Just to follow up in case it helps someone else. 

I was able to use the docker cp command to copy from the container to the local filesystem. Worked perfectly!

 

Scott