I have an USB disk connected to a FritzBox which is acting as a NAS.
The USB share is mounted in a folder of the internal filespace of the FritzBox.
When I access the disk via samba, only the free space of the internal FritzBox memory is reported, not that of the USB disk.
I read in forums that this is not happening under Windows, where the sum of internal memory and USB disk is reported.
For me this is a mayor issue as Deja Dup which I use for backups will not run a backup because of insufficient diskspace.
Samba only counts the free space in the root of the share. Sub-mounts are not counted. Please try exporting your usb disk as the root of your share. If that does not help, please take a look at "dfree command".
If that does not help, please re-open this bug again.