Docker Virtual Disk Location

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I am a new unRAID Pro user (v6.0-beta15) and am setting up Docker for the first time. I followed the Docker Guide here ( and setup my Docker image at /mnt/cache/docker.img in the Docker settings page. I then created a cache-only user share called "appdata" for my application data.


Now, when I browse to /mnt/user I see an /appdata folder and a docker.img file along with my other user share (/Media). I am just wondering if this is expected behavior, or if I have done something wrong with the Docker files. I do also see docker.img and /appdata in /mnt/cache (as I would expect) but I am just curious why they show up in both places (/mnt/cache and /mnt/user). Does this mean I have two copies, or is this a symbolic link thing? Any help to further my understanding of unRAID and Docker would be appreciated. Thank you.



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Yes, this is right, and also the way I have mine setup.


/mnt/user is the contents of the user shares including cache. There is also a /mnt/user0, which is the contents of the user shares excluding cache. The cache disk is considered part of the user shares so that anything written to cached sharea will still appear as part of the share even before it has been moved to the array.


/mnt/user0 also often confuses people when they first discover it. It can sometimes be useful to see what is in the array without the cache, but its main purpose is for the mover script to use. mover just moves any top level cache folders that are not cache-only to /mnt/user0, and so the cached files become array files.

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Thanks for the clarification. I was aware of the /mnt/user0 folder being used for storage before the mover moves the data to the array. I guess I was just surprised to see docker.img in the root of the /mnt/user folder. Sounds like it is as it should be.



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