I store some sensitive data on encrypted disk images. Sometimes for convenience I mount one of these disk image files (.dmg) over the LAN and occasionally forget to unmount it.
A problem arises where even if the client machine where it's mounted is put to sleep, the host still sees the disk image as being in use and will return the error:
The following disk images couldn't be opened Reason: Resource temporarily unavailable
To gain access to the image I need to physically find which computer it's mounted on, wake it from sleep and eject the image.
How can I force unmount an image which is mounted by a network client?