Docker Container reports free disk space for mapped Host folders incorrectly

[SiliconKid]

I ran into an interesting problem with my CouchPotato container.

 

I have 2 large MKV movies that I ripped from my original Blu-Ray discs with no compression, and are around 40 gig per movie.

 

I tried to get CouchPotato to do it's renaming thing on them and was promptly told by CouchPotato that there was not enough disk space to handle it.

 

On further investigation it appears that CouchPotato is actually talking about the amount of free disk space inside the Docker Host VM, because the free space reported for that in the unRAID UI matches the amount of disk space remaining reported in the CP log file.

 

The thing is, both the folder containing the source MKV files to be renamed, and the folder where renamed files is copied to by CP after renaming, are Host folders, on my unRAID array, which has 2.9 Terabytes of free space right now.

 

I'm mapping both of those locations into the container.

 

So CP is reporting the free space of completely the wrong thing altogether.

 

This could be a CP bug where it's looking at the free space of drive on which it is running when it shouldn't be, or this could be something else related to how these Docker Containers see the amount of available disk space when they look at a Host folder that is mapped into them.

 

Is a Docker Container even able to see how much free space is available in a location that is mapped into it from the host ? I can't find anything online that confirms or denies it.

 

Does anybody have any insight regarding this ?