Basics: Using persistent storage /data


#1

Hi there

I still have problems understanding how the persistant storage works.
So far I understand, that the /data is part of a docker volume, which is kind of an instance of a docker image…

And my resin app also runs in a docker volume, but another one, right?

When I do a git push resin master it builds everything. After that the image is deployed to the device. After the deploy resin will use docker to «mount» it

So only after the app is running the /data is available, because before there is no image and cannot be run?

Now there is a lot of description about mounting sd cards with persistent storage… https://docs.resin.io/learn/develop/runtime/#persistent-storage
But I think this does not even apply for my case.
I don’t have any additional USB or SD Card. I just have the one SD Card with my resinified raspberry system on it.
Is the assumption correct that the chapter about mounting /data is only important for additional SD Cards and USB sticks?

In my case, I just want to copy a file to the /data to be used by the application.
I tried to connect the SD Card to my mac with an app to mount ext4 linux file systems.

This does indeed show me 5 volumes, but I could not figure out which one would hold the /data folder.
Will I even see it by doing this, or do I have to mount it in a special way, as desribed in the documentation?

Thanks for any help on this matter…

Cheers

I’d also be happy to provide more information if needed, but at the moment, I don’t even know, what else could be important. o.O