Hi,
When I want mount a iso in my container I have this error :
mount: /media/iso/: mount failed: Unknown error -1
I use this command to mount :
mount -o loop iso.iso /media/iso/
The containers run with the lastest debian version.
No one can help ? 
I have the same thing as you
Hello,
Sorry for the silly question but the target directory exists ?
I am having the same problem -
mount -o loop /usr/Spectrum/custom/ISO/rhel-server-7.5-x86_64-dvd.iso /media/
mount: /usr/Spectrum/custom/ISO/rhel-server-7.5-x86_64-dvd.iso: failed to setup loop device: No such file or directory
The dev/sys loop stuff is where the problem is, but I have not yet found a solution either.
DonL
Yes, the first thing I’d check is “is the mount accessible”. So just mount and “cd” into it.
To access it from inside of a container you’ll need a volume attached. Assuming the iso is mounted to /media/iso, your Docker cmd would look something like this: “docker run -v /media/iso:/media/iso …”
Bare in mind that the OS inside the container also needs the /media/iso directory present … if not, create it or choose a different path.